content: /*
   * Copyright (c) 2006, 2021, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package openjdk.tools.javac.main;
  
  import java.io.FileWriter;
  import java.io.PrintWriter;
  import java.nio.file.Files;
  import java.nio.file.InvalidPathException;
  import java.nio.file.Path;
  import java.nio.file.Paths;
  import java.text.Collator;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.Comparator;
  import java.util.EnumSet;
  import java.util.Iterator;
  import java.util.LinkedHashSet;
  import java.util.Locale;
  import java.util.ServiceLoader;
  import java.util.Set;
  import java.util.StringJoiner;
  import java.util.TreeSet;
  import java.util.regex.Pattern;
  import java.util.stream.Collectors;
  import java.util.stream.StreamSupport;
  
  import jdkx.lang.model.SourceVersion;
  
  import openjdk.tools.doclint.DocLint;
  import openjdk.tools.javac.code.Lint;
  import openjdk.tools.javac.code.Lint.LintCategory;
  import openjdk.tools.javac.code.Source;
  import openjdk.tools.javac.code.Type;
  import openjdk.tools.javac.jvm.Profile;
  import openjdk.tools.javac.jvm.Target;
  import openjdk.tools.javac.platform.PlatformProvider;
  import openjdk.tools.javac.processing.JavacProcessingEnvironment;
  import openjdk.tools.javac.resources.CompilerProperties.Errors;
  import openjdk.tools.javac.util.Assert;
  import openjdk.tools.javac.util.Log;
  import openjdk.tools.javac.util.Log.PrefixKind;
  import openjdk.tools.javac.util.Log.WriterKind;
  import openjdk.tools.javac.util.Options;
  import openjdk.tools.javac.util.StringUtils;
  
  import static openjdk.tools.javac.main.Option.ChoiceKind.*;
  import static openjdk.tools.javac.main.Option.OptionGroup.*;
  import static openjdk.tools.javac.main.Option.OptionKind.*;
  
  /**
   * Options for javac.
   * The specific Option to handle a command-line option can be found by calling
   * {@link #lookup}, which search some or all of the members of this enum in order,
   * looking for the first {@link #matches match}.
   * The action for an Option is performed {@link #handleOption}, which determines
   * whether an argument is needed and where to find it;
   * {@code handleOption} then calls {@link #process process} providing a suitable
   * {@link OptionHelper} to provide access the compiler state.
   *
   * <p><b>This is NOT part of any supported API.
   * If you write code that depends on this, you do so at your own
   * risk.  This code and its internal interfaces are subject to change
   * or deletion without notice.</b></p>
   */
  public enum Option {
      G("-g", "opt.g", STANDARD, BASIC),
  
      G_NONE("-g:none", "opt.g.none", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option) {
              helper.put("-g:", "none");
          }
      },
  
      G_CUSTOM("-g:",  "opt.g.lines.vars.source",
              STANDARD, BASIC, ANYOF, "lines", "vars", "source"),
  
      XLINT("-Xlint", "opt.Xlint", EXTENDED, BASIC),
  
      XLINT_CUSTOM("-Xlint:", "opt.arg.Xlint", "opt.Xlint.custom", EXTENDED, BASIC, ANYOF, getXLintChoices()),
  
      XDOCLINT("-Xdoclint", "opt.Xdoclint", EXTENDED, BASIC),
  
      XDOCLINT_CUSTOM("-Xdoclint:", "opt.Xdoclint.subopts", "opt.Xdoclint.custom", EXTENDED, BASIC) {
          @Override
          public boolean matches(String option) {
              return DocLint.newDocLint().isValidOption(
              option.replace(XDOCLINT_CUSTOM.primaryName, DocLint.XMSGS_CUSTOM_PREFIX));
              //return new DocLint().isValidOption(
                      //option.replace(XDOCLINT_CUSTOM.primaryName, DocLint.XMSGS_CUSTOM_PREFIX));
          }
  
          @Override
          public void process(OptionHelper helper, String option, String arg) {
              String prev = helper.get(XDOCLINT_CUSTOM);
              String next = (prev == null) ? arg : (prev + " " + arg);
              helper.put(XDOCLINT_CUSTOM.primaryName, next);
          }
      },
  
      XDOCLINT_PACKAGE("-Xdoclint/package:", "opt.Xdoclint.package.args", "opt.Xdoclint.package.desc", EXTENDED, BASIC) {
          @Override
          public boolean matches(String option) {
              return DocLint.newDocLint().isValidOption(
              option.replace(XDOCLINT_PACKAGE.primaryName, DocLint.XCHECK_PACKAGE));
              //return new DocLint().isValidOption(
                      //option.replace(XDOCLINT_PACKAGE.primaryName, DocLint.XCHECK_PACKAGE));
          }
  
          @Override
          public void process(OptionHelper helper, String option, String arg) {
              String prev = helper.get(XDOCLINT_PACKAGE);
              String next = (prev == null) ? arg : (prev + "," + arg);
              helper.put(XDOCLINT_PACKAGE.primaryName, next);
          }
      },
  
      // -nowarn is retained for command-line backward compatibility
      NOWARN("-nowarn", "opt.nowarn", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option) {
              helper.put("-Xlint:none", option);
          }
      },
  
      VERBOSE("-verbose", "opt.verbose", STANDARD, BASIC),
  
      // -deprecation is retained for command-line backward compatibility
      DEPRECATION("-deprecation", "opt.deprecation", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option) {
              helper.put("-Xlint:deprecation", option);
          }
      },
  
      CLASS_PATH("--class-path -classpath -cp", "opt.arg.path", "opt.classpath", STANDARD, FILEMANAGER),
  
      SOURCE_PATH("--source-path -sourcepath", "opt.arg.path", "opt.sourcepath", STANDARD, FILEMANAGER),
  
      MODULE_SOURCE_PATH("--module-source-path", "opt.arg.mspath", "opt.modulesourcepath", STANDARD, FILEMANAGER) {
          // The deferred file manager diagnostics mechanism assumes a single value per option,
          // but --module-source-path-module can be used multiple times, once in the old form
          // and once per module in the new form.  Therefore we compose an overall value for the
          // option containing the individual values given on the command line, separated by NULL.
          // The standard file manager code knows to split apart the NULL-separated components.
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              }
              Pattern moduleSpecificForm = getPattern();
              String prev = helper.get(MODULE_SOURCE_PATH);
              if (prev == null) {
                  super.process(helper, option, arg);
              } else  if (moduleSpecificForm.matcher(arg).matches()) {
                  String argModule = arg.substring(0, arg.indexOf('='));
                  boolean isRepeated = Arrays.stream(prev.split("\0"))
                          .filter(s -> moduleSpecificForm.matcher(s).matches())
                          .map(s -> s.substring(0, s.indexOf('=')))
                          .anyMatch(s -> s.equals(argModule));
                  if (isRepeated) {
                      throw helper.newInvalidValueException(Errors.RepeatedValueForModuleSourcePath(argModule));
                  } else {
                      super.process(helper, option, prev + '\0' + arg);
                  }
              } else {
                  boolean isPresent = Arrays.stream(prev.split("\0"))
                          .anyMatch(s -> !moduleSpecificForm.matcher(s).matches());
                  if (isPresent) {
                      throw helper.newInvalidValueException(Errors.MultipleValuesForModuleSourcePath);
                  } else {
                      super.process(helper, option, prev + '\0' + arg);
                  }
              }
          }
  
          @Override
          public Pattern getPattern() {
              return Pattern.compile("([\\p{Alnum}$_.]+)=(.*)");
          }
      },
  
      MODULE_PATH("--module-path -p", "opt.arg.path", "opt.modulepath", STANDARD, FILEMANAGER),
  
      UPGRADE_MODULE_PATH("--upgrade-module-path", "opt.arg.path", "opt.upgrademodulepath", STANDARD, FILEMANAGER),
  
      SYSTEM("--system", "opt.arg.jdk", "opt.system", STANDARD, FILEMANAGER),
  
      PATCH_MODULE("--patch-module", "opt.arg.patch", "opt.patch", EXTENDED, FILEMANAGER) {
          // The deferred file manager diagnostics mechanism assumes a single value per option,
          // but --patch-module can be used multiple times, once per module. Therefore we compose
          // a value for the option containing the last value specified for each module, and separate
          // the module=path pairs by an invalid path character, NULL.
          // The standard file manager code knows to split apart the NULL-separated components.
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              } else if (getPattern().matcher(arg).matches()) {
                  String prev = helper.get(PATCH_MODULE);
                  if (prev == null) {
                      super.process(helper, option, arg);
                  } else {
                      String argModulePackage = arg.substring(0, arg.indexOf('='));
                      boolean isRepeated = Arrays.stream(prev.split("\0"))
                              .map(s -> s.substring(0, s.indexOf('=')))
                              .collect(Collectors.toSet())
                              .contains(argModulePackage);
                      if (isRepeated) {
                          throw helper.newInvalidValueException(Errors.RepeatedValueForPatchModule(argModulePackage));
                      } else {
                          super.process(helper, option, prev + '\0' + arg);
                      }
                  }
              } else {
                  throw helper.newInvalidValueException(Errors.BadValueForOption(option, arg));
              }
          }
  
          @Override
          public Pattern getPattern() {
              return Pattern.compile("([^/]+)=(,*[^,].*)");
          }
      },
  
      BOOT_CLASS_PATH("--boot-class-path -bootclasspath", "opt.arg.path", "opt.bootclasspath", STANDARD, FILEMANAGER) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              helper.remove("-Xbootclasspath/p:");
              helper.remove("-Xbootclasspath/a:");
              super.process(helper, option, arg);
          }
      },
  
      XBOOTCLASSPATH_PREPEND("-Xbootclasspath/p:", "opt.arg.path", "opt.Xbootclasspath.p", EXTENDED, FILEMANAGER),
  
      XBOOTCLASSPATH_APPEND("-Xbootclasspath/a:", "opt.arg.path", "opt.Xbootclasspath.a", EXTENDED, FILEMANAGER),
  
      XBOOTCLASSPATH("-Xbootclasspath:", "opt.arg.path", "opt.bootclasspath", EXTENDED, FILEMANAGER) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              helper.remove("-Xbootclasspath/p:");
              helper.remove("-Xbootclasspath/a:");
              super.process(helper, "-bootclasspath", arg);
          }
      },
  
      EXTDIRS("-extdirs", "opt.arg.dirs", "opt.extdirs", STANDARD, FILEMANAGER),
  
      DJAVA_EXT_DIRS("-Djava.ext.dirs=", "opt.arg.dirs", "opt.extdirs", EXTENDED, FILEMANAGER) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              EXTDIRS.process(helper, "-extdirs", arg);
          }
      },
  
      ENDORSEDDIRS("-endorseddirs", "opt.arg.dirs", "opt.endorseddirs", STANDARD, FILEMANAGER),
  
      DJAVA_ENDORSED_DIRS("-Djava.endorsed.dirs=", "opt.arg.dirs", "opt.endorseddirs", EXTENDED, FILEMANAGER) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              ENDORSEDDIRS.process(helper, "-endorseddirs", arg);
          }
      },
  
      PROC("-proc:", "opt.proc.none.only", STANDARD, BASIC,  ONEOF, "none", "only"),
  
      PROCESSOR("-processor", "opt.arg.class.list", "opt.processor", STANDARD, BASIC),
  
      PROCESSOR_PATH("--processor-path -processorpath", "opt.arg.path", "opt.processorpath", STANDARD, FILEMANAGER),
  
      PROCESSOR_MODULE_PATH("--processor-module-path", "opt.arg.path", "opt.processormodulepath", STANDARD, FILEMANAGER),
  
      PARAMETERS("-parameters","opt.parameters", STANDARD, BASIC),
  
      D("-d", "opt.arg.directory", "opt.d", STANDARD, FILEMANAGER),
  
      S("-s", "opt.arg.directory", "opt.sourceDest", STANDARD, FILEMANAGER),
  
      H("-h", "opt.arg.directory", "opt.headerDest", STANDARD, FILEMANAGER),
  
      IMPLICIT("-implicit:", "opt.implicit", STANDARD, BASIC, ONEOF, "none", "class"),
  
      ENCODING("-encoding", "opt.arg.encoding", "opt.encoding", STANDARD, FILEMANAGER),
  
      SOURCE("--source -source", "opt.arg.release", "opt.source", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String operand) throws InvalidValueException {
              Source source = Source.lookup(operand);
              if (source == null) {
                  throw helper.newInvalidValueException(Errors.InvalidSource(operand));
              }
              super.process(helper, option, operand);
          }
  
          @Override
          protected void help(Log log) {
              StringJoiner sj = new StringJoiner(", ");
              for(Source source :  Source.values()) {
                  if (source.isSupported())
                      sj.add(source.name);
              }
              super.help(log, log.localize(PrefixKind.JAVAC, descrKey, sj.toString()));
          }
      },
  
      TARGET("--target -target", "opt.arg.release", "opt.target", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String operand) throws InvalidValueException {
              Target target = Target.lookup(operand);
              if (target == null) {
                  throw helper.newInvalidValueException(Errors.InvalidTarget(operand));
              }
              super.process(helper, option, operand);
          }
  
          @Override
          protected void help(Log log) {
              StringJoiner sj = new StringJoiner(", ");
              for(Target target :  Target.values()) {
                  if (target.isSupported())
                      sj.add(target.name);
              }
              super.help(log, log.localize(PrefixKind.JAVAC, descrKey, sj.toString()));
          }
      },
  
      RELEASE("--release", "opt.arg.release", "opt.release", STANDARD, BASIC) {
          @Override
          protected void help(Log log) {
              Iterable<PlatformProvider> providers =
                      ServiceLoader.load(PlatformProvider.class, Arguments.class.getClassLoader());
              Set<String> platforms = StreamSupport.stream(providers.spliterator(), false)
                                                   .flatMap(provider -> StreamSupport.stream(provider.getSupportedPlatformNames()
                                                                                                     .spliterator(),
                                                                                             false))
                                                   .collect(Collectors.toCollection(LinkedHashSet :: new));
  
              StringBuilder targets = new StringBuilder();
              String delim = "";
              for (String platform : platforms) {
                  targets.append(delim);
                  targets.append(platform);
                  delim = ", ";
              }
  
              super.help(log, log.localize(PrefixKind.JAVAC, descrKey, targets.toString()));
          }
      },
  
      PREVIEW("--enable-preview", "opt.preview", STANDARD, BASIC),
  
      PROFILE("-profile", "opt.arg.profile", "opt.profile", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String operand) throws InvalidValueException {
              Profile profile = Profile.lookup(operand);
              if (profile == null) {
                  throw helper.newInvalidValueException(Errors.InvalidProfile(operand));
              }
              super.process(helper, option, operand);
          }
      },
  
      VERSION("--version -version", "opt.version", STANDARD, INFO) {
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              Log log = helper.getLog();
              String ownName = helper.getOwnName();
              log.printLines(WriterKind.STDOUT, PrefixKind.JAVAC, "version", ownName,  JavaCompiler.version());
              super.process(helper, option);
          }
      },
  
      FULLVERSION("--full-version -fullversion", null, HIDDEN, INFO) {
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              Log log = helper.getLog();
              String ownName = helper.getOwnName();
              log.printLines(WriterKind.STDOUT, PrefixKind.JAVAC, "fullVersion", ownName,  JavaCompiler.fullVersion());
              super.process(helper, option);
          }
      },
  
      // Note: -h is already taken for "native header output directory".
      HELP("--help -help -?", "opt.help", STANDARD, INFO) {
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              Log log = helper.getLog();
              String ownName = helper.getOwnName();
              log.printLines(WriterKind.STDOUT, PrefixKind.JAVAC, "msg.usage.header", ownName);
              showHelp(log, OptionKind.STANDARD);
              log.printNewline(WriterKind.STDOUT);
              super.process(helper, option);
          }
      },
  
      A("-A", "opt.arg.key.equals.value", "opt.A", STANDARD, BASIC, ArgKind.ADJACENT) {
          @Override
          public boolean matches(String arg) {
              return arg.startsWith("-A");
          }
  
          @Override
          public boolean hasArg() {
              return false;
          }
          // Mapping for processor options created in
          // JavacProcessingEnvironment
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              int argLength = option.length();
              if (argLength == 2) {
                  throw helper.newInvalidValueException(Errors.EmptyAArgument);
              }
              int sepIndex = option.indexOf('=');
              String key = option.substring(2, (sepIndex != -1 ? sepIndex : argLength) );
              if (!JavacProcessingEnvironment.isValidOptionName(key)) {
                  throw helper.newInvalidValueException(Errors.InvalidAKey(option));
              }
              helper.put(option, option);
          }
      },
  
      DEFAULT_MODULE_FOR_CREATED_FILES("--default-module-for-created-files",
                                       "opt.arg.default.module.for.created.files",
                                       "opt.default.module.for.created.files", EXTENDED, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              String prev = helper.get(DEFAULT_MODULE_FOR_CREATED_FILES);
              if (prev != null) {
                  throw helper.newInvalidValueException(Errors.OptionTooMany(DEFAULT_MODULE_FOR_CREATED_FILES.primaryName));
              } else if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              } else if (getPattern().matcher(arg).matches()) {
                  helper.put(DEFAULT_MODULE_FOR_CREATED_FILES.primaryName, arg);
              } else {
                  throw helper.newInvalidValueException(Errors.BadValueForOption(option, arg));
              }
          }
  
          @Override
          public Pattern getPattern() {
              return Pattern.compile("[^,].*");
          }
      },
  
      X("--help-extra -X", "opt.X", STANDARD, INFO) {
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              Log log = helper.getLog();
              showHelp(log, OptionKind.EXTENDED);
              log.printNewline(WriterKind.STDOUT);
              log.printLines(WriterKind.STDOUT, PrefixKind.JAVAC, "msg.usage.nonstandard.footer");
              super.process(helper, option);
          }
      },
  
      HELP_LINT("--help-lint", "opt.help.lint", EXTENDED, INFO) {
          private final String LINT_KEY_FORMAT = SMALL_INDENT + SMALL_INDENT + "%-" +
                  (DEFAULT_SYNOPSIS_WIDTH - LARGE_INDENT.length()) + "s %s";
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              Log log = helper.getLog();
              log.printRawLines(WriterKind.STDOUT, log.localize(PrefixKind.JAVAC, "opt.help.lint.header"));
              log.printRawLines(WriterKind.STDOUT,
                                String.format(LINT_KEY_FORMAT,
                                              "all",
                                              log.localize(PrefixKind.JAVAC, "opt.Xlint.all")));
              for (LintCategory lc : LintCategory.values()) {
                  log.printRawLines(WriterKind.STDOUT,
                                    String.format(LINT_KEY_FORMAT,
                                                  lc.option,
                                                  log.localize(PrefixKind.JAVAC,
                                                               "opt.Xlint.desc." + lc.option)));
              }
              log.printRawLines(WriterKind.STDOUT,
                                String.format(LINT_KEY_FORMAT,
                                              "none",
                                              log.localize(PrefixKind.JAVAC, "opt.Xlint.none")));
              super.process(helper, option);
          }
      },
  
      // This option exists only for the purpose of documenting itself.
      // It's actually implemented by the launcher.
      J("-J", "opt.arg.flag", "opt.J", STANDARD, INFO, ArgKind.ADJACENT) {
          @Override
          public void process(OptionHelper helper, String option) {
              throw new AssertionError("the -J flag should be caught by the launcher.");
          }
      },
  
      MOREINFO("-moreinfo", null, HIDDEN, BASIC) {
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              Type.moreInfo = true;
              super.process(helper, option);
          }
      },
  
      // treat warnings as errors
      WERROR("-Werror", "opt.Werror", STANDARD, BASIC),
  
      // prompt after each error
      // new Option("-prompt",                                        "opt.prompt"),
      PROMPT("-prompt", null, HIDDEN, BASIC),
  
      // dump stack on error
      DOE("-doe", null, HIDDEN, BASIC),
  
      // output source after type erasure
      PRINTSOURCE("-printsource", null, HIDDEN, BASIC),
  
      // display warnings for generic unchecked operations
      WARNUNCHECKED("-warnunchecked", null, HIDDEN, BASIC) {
          @Override
          public void process(OptionHelper helper, String option) {
              helper.put("-Xlint:unchecked", option);
          }
      },
  
      XMAXERRS("-Xmaxerrs", "opt.arg.number", "opt.maxerrs", EXTENDED, BASIC),
  
      XMAXWARNS("-Xmaxwarns", "opt.arg.number", "opt.maxwarns", EXTENDED, BASIC),
  
      XSTDOUT("-Xstdout", "opt.arg.file", "opt.Xstdout", EXTENDED, INFO) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              try {
                  Log log = helper.getLog();
                  log.setWriters(new PrintWriter(new FileWriter(arg), true));
              } catch (java.io.IOException e) {
                  throw helper.newInvalidValueException(Errors.ErrorWritingFile(arg, e.getMessage()));
              }
              super.process(helper, option, arg);
          }
      },
  
      XPRINT("-Xprint", "opt.print", EXTENDED, BASIC),
  
      XPRINTROUNDS("-XprintRounds", "opt.printRounds", EXTENDED, BASIC),
  
      XPRINTPROCESSORINFO("-XprintProcessorInfo", "opt.printProcessorInfo", EXTENDED, BASIC),
  
      XPREFER("-Xprefer:", "opt.prefer", EXTENDED, BASIC, ONEOF, "source", "newer"),
  
      XXUSERPATHSFIRST("-XXuserPathsFirst", "opt.userpathsfirst", HIDDEN, BASIC),
  
      // see enum PkgInfo
      XPKGINFO("-Xpkginfo:", "opt.pkginfo", EXTENDED, BASIC, ONEOF, "always", "legacy", "nonempty"),
  
      /* -O is a no-op, accepted for backward compatibility. */
      O("-O", null, HIDDEN, BASIC),
  
      /* -Xjcov produces tables to support the code coverage tool jcov. */
      XJCOV("-Xjcov", null, HIDDEN, BASIC),
  
      PLUGIN("-Xplugin:", "opt.arg.plugin", "opt.plugin", EXTENDED, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String p) {
              String prev = helper.get(PLUGIN);
              helper.put(PLUGIN.primaryName, (prev == null) ? p : prev + '\0' + p);
          }
      },
  
      XDIAGS("-Xdiags:", "opt.diags", EXTENDED, BASIC, ONEOF, "compact", "verbose"),
  
      DEBUG("--debug", null, HIDDEN, BASIC, ArgKind.REQUIRED) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              HiddenGroup.DEBUG.process(helper, option, arg);
          }
      },
  
      SHOULDSTOP("--should-stop", null, HIDDEN, BASIC, ArgKind.REQUIRED) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              HiddenGroup.SHOULDSTOP.process(helper, option, arg);
          }
      },
  
      DIAGS("--diags", null, HIDDEN, BASIC, ArgKind.REQUIRED) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              HiddenGroup.DIAGS.process(helper, option, arg);
          }
      },
  
      /* This is a back door to the compiler's option table.
       * -XDx=y sets the option x to the value y.
       * -XDx sets the option x to the value x.
       */
      XD("-XD", null, HIDDEN, BASIC) {
          @Override
          public boolean matches(String s) {
              return s.startsWith(primaryName);
          }
          @Override
          public void process(OptionHelper helper, String option) {
              process(helper, option, option.substring(primaryName.length()));
          }
  
          @Override
          public void process(OptionHelper helper, String option, String arg) {
              int eq = arg.indexOf('=');
              String key = (eq < 0) ? arg : arg.substring(0, eq);
              String value = (eq < 0) ? arg : arg.substring(eq+1);
              helper.put(key, value);
          }
      },
  
      ADD_EXPORTS("--add-exports", "opt.arg.addExports", "opt.addExports", EXTENDED, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              } else if (getPattern().matcher(arg).matches()) {
                  String prev = helper.get(ADD_EXPORTS);
                  helper.put(ADD_EXPORTS.primaryName, (prev == null) ? arg : prev + '\0' + arg);
              } else {
                  throw helper.newInvalidValueException(Errors.BadValueForOption(option, arg));
              }
          }
  
          @Override
          public Pattern getPattern() {
              return Pattern.compile("([^/]+)/([^=]+)=(,*[^,].*)");
          }
      },
  
      ADD_OPENS("--add-opens", null, null, HIDDEN, BASIC),
  
      ADD_READS("--add-reads", "opt.arg.addReads", "opt.addReads", EXTENDED, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              } else if (getPattern().matcher(arg).matches()) {
                  String prev = helper.get(ADD_READS);
                  helper.put(ADD_READS.primaryName, (prev == null) ? arg : prev + '\0' + arg);
              } else {
                  throw helper.newInvalidValueException(Errors.BadValueForOption(option, arg));
              }
          }
  
          @Override
          public Pattern getPattern() {
              return Pattern.compile("([^=]+)=(,*[^,].*)");
          }
      },
  
      MODULE("--module -m", "opt.arg.m", "opt.m", STANDARD, BASIC),
  
      ADD_MODULES("--add-modules", "opt.arg.addmods", "opt.addmods", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              } else if (getPattern().matcher(arg).matches()) {
                  String prev = helper.get(ADD_MODULES);
                  // since the individual values are simple names, we can simply join the
                  // values of multiple --add-modules options with ','
                  helper.put(ADD_MODULES.primaryName, (prev == null) ? arg : prev + ',' + arg);
              } else {
                  throw helper.newInvalidValueException(Errors.BadValueForOption(option, arg));
              }
          }
  
          @Override
          public Pattern getPattern() {
              return Pattern.compile(",*[^,].*");
          }
      },
  
      LIMIT_MODULES("--limit-modules", "opt.arg.limitmods", "opt.limitmods", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              } else if (getPattern().matcher(arg).matches()) {
                  helper.put(LIMIT_MODULES.primaryName, arg); // last one wins
              } else {
                  throw helper.newInvalidValueException(Errors.BadValueForOption(option, arg));
              }
          }
  
          @Override
          public Pattern getPattern() {
              return Pattern.compile(",*[^,].*");
          }
      },
  
      MODULE_VERSION("--module-version", "opt.arg.module.version", "opt.module.version", STANDARD, BASIC) {
          @Override
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              if (arg.isEmpty()) {
                  throw helper.newInvalidValueException(Errors.NoValueForOption(option));
              }
              super.process(helper, option, arg);
          }
      },
  
      // This option exists only for the purpose of documenting itself.
      // It's actually implemented by the CommandLine class.
      AT("@", "opt.arg.file", "opt.AT", STANDARD, INFO, ArgKind.ADJACENT) {
          @Override
          public void process(OptionHelper helper, String option) {
              throw new AssertionError("the @ flag should be caught by CommandLine.");
          }
      },
  
      // Standalone positional argument: source file or type name.
      SOURCEFILE("sourcefile", null, HIDDEN, INFO) {
          @Override
          public boolean matches(String s) {
              if (s.endsWith(".java"))  // Java source file
                  return true;
              int sep = s.indexOf('/');
              if (sep != -1) {
                  return SourceVersion.isName(s.substring(0, sep))
                          && SourceVersion.isName(s.substring(sep + 1));
              } else {
                  return SourceVersion.isName(s);   // Legal type name
              }
          }
          @Override
          public void process(OptionHelper helper, String option) throws InvalidValueException {
              if (option.endsWith(".java") ) {
                  try {
                      Path p = Paths.get(option);
                      if (!Files.exists(p)) {
                          throw helper.newInvalidValueException(Errors.FileNotFound(p.toString()));
                      }
                      if (!Files.isRegularFile(p)) {
                          throw helper.newInvalidValueException(Errors.FileNotFile(p));
                      }
                      helper.addFile(p);
                  } catch (InvalidPathException ex) {
                      throw helper.newInvalidValueException(Errors.InvalidPath(option));
                  }
              } else {
                  helper.addClassName(option);
              }
          }
      },
  
      MULTIRELEASE("--multi-release", "opt.arg.multi-release", "opt.multi-release", HIDDEN, FILEMANAGER);
  
      /**
       * This exception is thrown when an invalid value is given for an option.
       * The detail string gives a detailed, localized message, suitable for use
       * in error messages reported to the user.
       */
      public static class InvalidValueException extends Exception {
          private static final long serialVersionUID = -1;
  
          public InvalidValueException(String msg) {
              super(msg);
          }
  
          public InvalidValueException(String msg, Throwable cause) {
              super(msg, cause);
          }
      }
  
      /**
       * The kind of argument, if any, accepted by this option. The kind is augmented
       * by characters in the name of the option.
       */
      public enum ArgKind {
          /** This option does not take any argument. */
          NONE,
  
  // Not currently supported
  //        /**
  //         * This option takes an optional argument, which may be provided directly after an '='
  //         * separator, or in the following argument position if that word does not itself appear
  //         * to be the name of an option.
  //         */
  //        OPTIONAL,
  
          /**
           * This option takes an argument.
           * If the name of option ends with ':' or '=', the argument must be provided directly
           * after that separator.
           * Otherwise, it may appear after an '=' or in the following argument position.
           */
          REQUIRED,
  
          /**
           * This option takes an argument immediately after the option name, with no separator
           * character.
           */
          ADJACENT
      }
  
      /**
       * The kind of an Option. This is used by the -help and -X options.
       */
      public enum OptionKind {
          /** A standard option, documented by -help. */
          STANDARD,
          /** An extended option, documented by -X. */
          EXTENDED,
          /** A hidden option, not documented. */
          HIDDEN,
      }
  
      /**
       * The group for an Option. This determines the situations in which the
       * option is applicable.
       */
      enum OptionGroup {
          /** A basic option, available for use on the command line or via the
           *  Compiler API. */
          BASIC,
          /** An option for javac's standard JavaFileManager. Other file managers
           *  may or may not support these options. */
          FILEMANAGER,
          /** A command-line option that requests information, such as -help. */
          INFO,
          /** A command-line "option" representing a file or class name. */
          OPERAND
      }
  
      /**
       * The kind of choice for "choice" options.
       */
      enum ChoiceKind {
          /** The expected value is exactly one of the set of choices. */
          ONEOF,
          /** The expected value is one of more of the set of choices. */
          ANYOF
      }
  
      enum HiddenGroup {
          DIAGS("diags"),
          DEBUG("debug"),
          SHOULDSTOP("should-stop");
  
          final String text;
  
          HiddenGroup(String text) {
              this.text = text;
          }
  
          public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
              String[] subOptions = arg.split(";");
              for (String subOption : subOptions) {
                  subOption = text + "." + subOption.trim();
                  XD.process(helper, subOption, subOption);
              }
          }
      }
  
      /**
       * The "primary name" for this option.
       * This is the name that is used to put values in the {@link Options} table.
       */
      public final String primaryName;
  
      /**
       * The set of names (primary name and aliases) for this option.
       * Note that some names may end in a separator, to indicate that an argument must immediately
       * follow the separator (and cannot appear in the following argument position.
       */
      public final String[] names;
  
      /** Documentation key for arguments. */
      protected final String argsNameKey;
  
      /** Documentation key for description.
       */
      protected final String descrKey;
  
      /** The kind of this option. */
      private final OptionKind kind;
  
      /** The group for this option. */
      private final OptionGroup group;
  
      /** The kind of argument for this option. */
      private final ArgKind argKind;
  
      /** The kind of choices for this option, if any. */
      private final ChoiceKind choiceKind;
  
      /** The choices for this option, if any. */
      private final Set<String> choices;
  
      /**
       * Looks up the first option matching the given argument in the full set of options.
       * @param arg the argument to be matches
       * @return the first option that matches, or null if none.
       */
      public static Option lookup(String arg) {
          return lookup(arg, EnumSet.allOf(Option.class));
      }
  
      /**
       * Looks up the first option matching the given argument within a set of options.
       * @param arg the argument to be matched
       * @param options the set of possible options
       * @return the first option that matches, or null if none.
       */
      public static Option lookup(String arg, Set<Option> options) {
          for (Option option: options) {
              if (option.matches(arg))
                  return option;
          }
          return null;
      }
  
      /**
       * Writes the "command line help" for given kind of option to the log.
       * @param log the log
       * @param kind  the kind of options to select
       */
      private static void showHelp(Log log, OptionKind kind) {
          Comparator<Option> comp = new Comparator<Option>() {
              final Collator collator = Collator.getInstance(Locale.US);
              { collator.setStrength(Collator.PRIMARY); }
  
              @Override
              public int compare(Option o1, Option o2) {
                  return collator.compare(o1.primaryName, o2.primaryName);
              }
          };
  
          getJavaCompilerOptions()
                  .stream()
                  .filter(o -> o.kind == kind)
                  .sorted(comp)
                  .forEach(o -> {
                      o.help(log);
                  });
      }
  
      Option(String text, String descrKey,
              OptionKind kind, OptionGroup group) {
          this(text, null, descrKey, kind, group, null, null, ArgKind.NONE);
      }
  
      Option(String text, String descrKey,
              OptionKind kind, OptionGroup group, ArgKind argKind) {
          this(text, null, descrKey, kind, group, null, null, argKind);
      }
  
      Option(String text, String argsNameKey, String descrKey,
              OptionKind kind, OptionGroup group) {
          this(text, argsNameKey, descrKey, kind, group, null, null, ArgKind.REQUIRED);
      }
  
      Option(String text, String argsNameKey, String descrKey,
              OptionKind kind, OptionGroup group, ArgKind ak) {
          this(text, argsNameKey, descrKey, kind, group, null, null, ak);
      }
  
      Option(String text, String argsNameKey, String descrKey, OptionKind kind, OptionGroup group,
              ChoiceKind choiceKind, Set<String> choices) {
          this(text, argsNameKey, descrKey, kind, group, choiceKind, choices, ArgKind.REQUIRED);
      }
  
      Option(String text, String descrKey,
              OptionKind kind, OptionGroup group,
              ChoiceKind choiceKind, String... choices) {
          this(text, null, descrKey, kind, group, choiceKind,
                  new LinkedHashSet<>(Arrays.asList(choices)), ArgKind.REQUIRED);
      }
  
      private Option(String text, String argsNameKey, String descrKey,
              OptionKind kind, OptionGroup group,
              ChoiceKind choiceKind, Set<String> choices,
              ArgKind argKind) {
          this.names = text.trim().split("\\s+");
          Assert.check(names.length >= 1);
          this.primaryName = names[0];
          this.argsNameKey = argsNameKey;
          this.descrKey = descrKey;
          this.kind = kind;
          this.group = group;
          this.choiceKind = choiceKind;
          this.choices = choices;
          this.argKind = argKind;
      }
  
      public String getPrimaryName() {
          return primaryName;
      }
  
      public OptionKind getKind() {
          return kind;
      }
  
      public ArgKind getArgKind() {
          return argKind;
      }
  
      public boolean hasArg() {
          return (argKind != ArgKind.NONE);
      }
  
      public boolean hasSeparateArg() {
          return getArgKind() == ArgKind.REQUIRED &&
                 !primaryName.endsWith(":") && !primaryName.endsWith("=");
      }
  
      public boolean matches(String option) {
          for (String name: names) {
              if (matches(option, name))
                  return true;
          }
          return false;
      }
  
      private boolean matches(String option, String name) {
          if (name.startsWith("--")) {
              return option.equals(name)
                      || hasArg() && option.startsWith(name + "=");
          }
  
          boolean hasSuffix = (argKind == ArgKind.ADJACENT)
                  || name.endsWith(":") || name.endsWith("=");
  
          if (!hasSuffix)
              return option.equals(name);
  
          if (!option.startsWith(name))
              return false;
  
          if (choices != null) {
              String arg = option.substring(name.length());
              if (choiceKind == ChoiceKind.ONEOF)
                  return choices.contains(arg);
              else {
                  for (String a: arg.split(",+")) {
                      if (!choices.contains(a))
                          return false;
                  }
              }
          }
  
          return true;
      }
  
      /**
       * Handles an option.
       * If an argument for the option is required, depending on spec of the option, it will be found
       * as part of the current arg (following ':' or '=') or in the following argument.
       * This is the recommended way to handle an option directly, instead of calling the underlying
       * {@link #process process} methods.
       * @param helper a helper to provide access to the environment
       * @param arg the arg string that identified this option
       * @param rest the remaining strings to be analysed
       * @throws InvalidValueException if the value of the option was invalid
       * @implNote The return value is the opposite of that used by {@link #process}.
       */
      public void handleOption(OptionHelper helper, String arg, Iterator<String> rest) throws InvalidValueException {
          if (hasArg()) {
              String option;
              String operand;
              int sep = findSeparator(arg);
              if (getArgKind() == Option.ArgKind.ADJACENT) {
                  option = primaryName; // aliases not supported
                  operand = arg.substring(primaryName.length());
              } else if (sep > 0) {
                  option = arg.substring(0, sep);
                  operand = arg.substring(sep + 1);
              } else {
                  if (!rest.hasNext()) {
                      throw helper.newInvalidValueException(Errors.ReqArg(this.primaryName));
                  }
                  option = arg;
                  operand = rest.next();
              }
              process(helper, option, operand);
          } else {
              process(helper, arg);
          }
      }
  
      /**
       * Processes an option that either does not need an argument,
       * or which contains an argument within it, following a separator.
       * @param helper a helper to provide access to the environment
       * @param option the option to be processed
       * @throws InvalidValueException if an error occurred
       */
      public void process(OptionHelper helper, String option) throws InvalidValueException {
          if (argKind == ArgKind.NONE) {
              process(helper, primaryName, option);
          } else {
              int sep = findSeparator(option);
              process(helper, primaryName, option.substring(sep + 1));
          }
      }
  
      /**
       * Processes an option by updating the environment via a helper object.
       * @param helper a helper to provide access to the environment
       * @param option the option to be processed
       * @param arg the value to associate with the option, or a default value
       *  to be used if the option does not otherwise take an argument.
       * @throws InvalidValueException if an error occurred
       */
      public void process(OptionHelper helper, String option, String arg) throws InvalidValueException {
          if (choices != null) {
              if (choiceKind == ChoiceKind.ONEOF) {
                  // some clients like to see just one of option+choice set
                  for (String s : choices)
                      helper.remove(primaryName + s);
                  String opt = primaryName + arg;
                  helper.put(opt, opt);
                  // some clients like to see option (without trailing ":")
                  // set to arg
                  String nm = primaryName.substring(0, primaryName.length() - 1);
                  helper.put(nm, arg);
              } else {
                  // set option+word for each word in arg
                  for (String a: arg.split(",+")) {
                      String opt = primaryName + a;
                      helper.put(opt, opt);
                  }
              }
          }
          helper.put(primaryName, arg);
          if (group == OptionGroup.FILEMANAGER)
              helper.handleFileManagerOption(this, arg);
      }
  
      /**
       * Returns a pattern to analyze the value for an option.
       * @return the pattern
       * @throws UnsupportedOperationException if an option does not provide a pattern.
       */
      public Pattern getPattern() {
          throw new UnsupportedOperationException();
      }
  
      /**
       * Scans a word to find the first separator character, either colon or equals.
       * @param word the word to be scanned
       * @return the position of the first':' or '=' character in the word,
       *  or -1 if none found
       */
      private static int findSeparator(String word) {
          for (int i = 0; i < word.length(); i++) {
              switch (word.charAt(i)) {
                  case ':': case '=':
                      return i;
              }
          }
          return -1;
      }
  
      /** The indent for the option synopsis. */
      private static final String SMALL_INDENT = "  ";
      /** The automatic indent for the description. */
      private static final String LARGE_INDENT = "        ";
      /** The space allowed for the synopsis, if the description is to be shown on the same line. */
      private static final int DEFAULT_SYNOPSIS_WIDTH = 28;
      /** The nominal maximum line length, when seeing if text will fit on a line. */
      private static final int DEFAULT_MAX_LINE_LENGTH = 80;
      /** The format for a single-line help entry. */
      private static final String COMPACT_FORMAT = SMALL_INDENT + "%-" + DEFAULT_SYNOPSIS_WIDTH + "s %s";
  
      /**
       * Writes help text for this option to the log.
       * @param log the log
       */
      protected void help(Log log) {
          help(log, log.localize(PrefixKind.JAVAC, descrKey));
      }
  
      protected void help(Log log, String descr) {
          String synopses = Arrays.stream(names)
                  .map(s -> helpSynopsis(s, log))
                  .collect(Collectors.joining(", "));
  
          // If option synopses and description fit on a single line of reasonable length,
          // display using COMPACT_FORMAT
          if (synopses.length() < DEFAULT_SYNOPSIS_WIDTH
                  && !descr.contains("\n")
                  && (SMALL_INDENT.length() + DEFAULT_SYNOPSIS_WIDTH + 1 + descr.length() <= DEFAULT_MAX_LINE_LENGTH)) {
              log.printRawLines(WriterKind.STDOUT, String.format(COMPACT_FORMAT, synopses, descr));
              return;
          }
  
          // If option synopses fit on a single line of reasonable length, show that;
          // otherwise, show 1 per line
          if (synopses.length() <= DEFAULT_MAX_LINE_LENGTH) {
              log.printRawLines(WriterKind.STDOUT, SMALL_INDENT + synopses);
          } else {
              for (String name: names) {
                  log.printRawLines(WriterKind.STDOUT, SMALL_INDENT + helpSynopsis(name, log));
              }
          }
  
          // Finally, show the description
          log.printRawLines(WriterKind.STDOUT, LARGE_INDENT + descr.replace("\n", "\n" + LARGE_INDENT));
      }
  
      /**
       * Composes the initial synopsis of one of the forms for this option.
       * @param name the name of this form of the option
       * @param log the log used to localize the description of the arguments
       * @return  the synopsis
       */
      private String helpSynopsis(String name, Log log) {
          StringBuilder sb = new StringBuilder();
          sb.append(name);
          if (argsNameKey == null) {
              if (choices != null) {
                  if (!name.endsWith(":"))
                      sb.append(" ");
                  String sep = "{";
                  for (String choice : choices) {
                      sb.append(sep);
                      sb.append(choice);
                      sep = ",";
                  }
                  sb.append("}");
              }
          } else {
              if (!name.matches(".*[=:]$") && argKind != ArgKind.ADJACENT)
                  sb.append(" ");
              sb.append(log.localize(PrefixKind.JAVAC, argsNameKey));
          }
  
          return sb.toString();
      }
  
      // For -XpkgInfo:value
      public enum PkgInfo {
          /**
           * Always generate package-info.class for every package-info.java file.
           * The file may be empty if there annotations with a RetentionPolicy
           * of CLASS or RUNTIME.  This option may be useful in conjunction with
           * build systems (such as Ant) that expect javac to generate at least
           * one .class file for every .java file.
           */
          ALWAYS,
          /**
           * Generate a package-info.class file if package-info.java contains
           * annotations. The file may be empty if all the annotations have
           * a RetentionPolicy of SOURCE.
           * This value is just for backwards compatibility with earlier behavior.
           * Either of the other two values are to be preferred to using this one.
           */
          LEGACY,
          /**
           * Generate a package-info.class file if and only if there are annotations
           * in package-info.java to be written into it.
           */
          NONEMPTY;
  
          public static PkgInfo get(Options options) {
              String v = options.get(XPKGINFO);
              return (v == null
                      ? PkgInfo.LEGACY
                      : PkgInfo.valueOf(StringUtils.toUpperCase(v)));
          }
      }
  
      private static Set<String> getXLintChoices() {
          Set<String> choices = new LinkedHashSet<>();
          choices.add("all");
          for (Lint.LintCategory c : Lint.LintCategory.values()) {
              choices.add(c.option);
              choices.add("-" + c.option);
          }
          choices.add("none");
          return choices;
      }
  
      /**
       * Returns the set of options supported by the command line tool.
       * @return the set of options.
       */
      static Set<Option> getJavaCompilerOptions() {
          return EnumSet.allOf(Option.class);
      }
  
      /**
       * Returns the set of options supported by the built-in file manager.
       * @return the set of options.
       */
      public static Set<Option> getJavacFileManagerOptions() {
          return getOptions(FILEMANAGER);
      }
  
      /**
       * Returns the set of options supported by this implementation of
       * the JavaCompiler API, via {@link JavaCompiler#getTask}.
       * @return the set of options.
       */
      public static Set<Option> getJavacToolOptions() {
          return getOptions(BASIC);
      }
  
      private static Set<Option> getOptions(OptionGroup group) {
          return Arrays.stream(Option.values())
                  .filter(o -> o.group == group)
                  .collect(Collectors.toCollection(() -> EnumSet.noneOf(Option.class)));
      }
  
  }
  