content: /*
   *  Licensed to the Apache Software Foundation (ASF) under one or more
   *  contributor license agreements.  See the NOTICE file distributed with
   *  this work for additional information regarding copyright ownership.
   *  The ASF licenses this file to You under the Apache License, Version 2.0
   *  (the "License"); you may not use this file except in compliance with
   *  the License.  You may obtain a copy of the License at
   *
   *      https://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   */
  package org.apache.tools.ant.types.resources;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.nio.file.Files;
  
  import org.apache.tools.ant.BuildException;
  import org.apache.tools.ant.Project;
  import org.apache.tools.ant.types.Reference;
  import org.apache.tools.ant.types.Resource;
  import org.apache.tools.ant.types.ResourceFactory;
  import org.apache.tools.ant.util.FileUtils;
  
  /**
   * A Resource representation of a File.
   * @since Ant 1.7
   */
  public class FileResource extends Resource implements Touchable, FileProvider,
          ResourceFactory, Appendable {
  
      private static final FileUtils FILE_UTILS = FileUtils.getFileUtils();
      private static final int NULL_FILE
          = Resource.getMagicNumber("null file".getBytes());
  
      private File file;
      private File baseDir;
  
      /**
       * Default constructor.
       */
      public FileResource() {
      }
  
      /**
       * Construct a new FileResource using the specified basedir and relative name.
       * @param b      the basedir as File.
       * @param name   the relative filename.
       */
      public FileResource(File b, String name) {
          this.baseDir = b;
          this.file = FILE_UTILS.resolveFile(b, name);
      }
  
      /**
       * Construct a new FileResource from a File.
       * @param f the File represented.
       */
      public FileResource(File f) {
          setFile(f);
      }
  
      /**
       * Create a new FileResource.
       * @param p Project
       * @param f File represented
       * @since Ant 1.8
       */
      public FileResource(Project p, File f) {
          this(f);
          setProject(p);
      }
  
      /**
       * Constructor for Ant attribute introspection.
       * @param p the Project against which to resolve <code>s</code>.
       * @param s the absolute or Project-relative filename as a String.
       * @see org.apache.tools.ant.IntrospectionHelper
       */
      public FileResource(Project p, String s) {
          this(p, p.resolveFile(s));
      }
  
      /**
       * Set the File for this FileResource.
       * @param f the File to be represented.
       */
      public void setFile(File f) {
          checkAttributesAllowed();
          file = f;
          if (f != null && (getBaseDir() == null || !FILE_UTILS.isLeadingPath(getBaseDir(), f))) {
              setBaseDir(f.getParentFile());
          }
      }
  
      /**
       * Get the file represented by this FileResource.
       * @return the File.
       */
      @Override
      public File getFile() {
          if (isReference()) {
              return getRef().getFile();
          }
          dieOnCircularReference();
          synchronized (this) {
              if (file == null) {
                  //try to resolve file set via basedir/name property setters:
                  File d = getBaseDir();
                  String n = super.getName();
                  if (n != null) {
                      setFile(FILE_UTILS.resolveFile(d, n));
                  }
              }
          }
          return file;
      }
  
      /**
       * Set the basedir for this FileResource.
       * @param b the basedir as File.
       */
      public void setBaseDir(File b) {
          checkAttributesAllowed();
          baseDir = b;
      }
  
      /**
       * Return the basedir to which the name is relative.
       * @return the basedir as File.
       */
      public File getBaseDir() {
          if (isReference()) {
              return getRef().getBaseDir();
          }
          dieOnCircularReference();
          return baseDir;
      }
  
      /**
       * Overrides the super version.
       * @param r the Reference to set.
       */
      @Override
      public void setRefid(Reference r) {
          if (file != null || baseDir != null) {
              throw tooManyAttributes();
          }
          super.setRefid(r);
      }
  
      /**
       * Get the name of this FileResource.  If the basedir is set,
       * the name will be relative to that.  Otherwise the basename
       * only will be returned.
       * @return the name of this resource.
       */
      @Override
      public String getName() {
          if (isReference()) {
              return getRef().getName();
          }
          File b = getBaseDir();
          return b == null ? getNotNullFile().getName()
              : FILE_UTILS.removeLeadingPath(b, getNotNullFile());
      }
  
      /**
       * Learn whether this file exists.
       * @return true if this resource exists.
       */
      @Override
      public boolean isExists() {
          return isReference() ? getRef().isExists()
              : getNotNullFile().exists();
      }
  
      /**
       * Get the modification time in milliseconds since 01.01.1970 .
       * @return 0 if the resource does not exist.
       */
      @Override
      public long getLastModified() {
          return isReference()
              ? getRef().getLastModified()
              : getNotNullFile().lastModified();
      }
  
      /**
       * Learn whether the resource is a directory.
       * @return boolean flag indicating if the resource is a directory.
       */
      @Override
      public boolean isDirectory() {
          return isReference() ? getRef().isDirectory()
              : getNotNullFile().isDirectory();
      }
  
      /**
       * Get the size of this Resource.
       * @return the size, as a long, 0 if the Resource does not exist.
       */
      @Override
      public long getSize() {
          return isReference() ? getRef().getSize()
              : getNotNullFile().length();
      }
  
      /**
       * Return an InputStream for reading the contents of this Resource.
       * @return an InputStream object.
       * @throws IOException if an error occurs.
       */
      @Override
      public InputStream getInputStream() throws IOException {
          return isReference() ? getRef().getInputStream()
              : Files.newInputStream(getNotNullFile().toPath());
      }
  
      /**
       * Get an OutputStream for the Resource.
       * @return an OutputStream to which content can be written.
       * @throws IOException if unable to provide the content of this
       *         Resource as a stream.
       * @throws UnsupportedOperationException if OutputStreams are not
       *         supported for this Resource type.
       */
      @Override
      public OutputStream getOutputStream() throws IOException {
          if (isReference()) {
              return getRef().getOutputStream();
          }
          return getOutputStream(false);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public OutputStream getAppendOutputStream() throws IOException {
          if (isReference()) {
              return getRef().getAppendOutputStream();
          }
          return getOutputStream(true);
      }
  
      private OutputStream getOutputStream(boolean append) throws IOException {
          File f = getNotNullFile();
          if (f.exists()) {
              if (Files.isSymbolicLink(f.toPath()) && f.isFile() && !append) {
                  // https://bz.apache.org/bugzilla/show_bug.cgi?id=624
                  f.delete();
              }
          } else {
              File p = f.getParentFile();
              if (p != null && !(p.exists())) {
                  p.mkdirs();
              }
          }
          return FileUtils.newOutputStream(f.toPath(), append);
      }
  
      /**
       * Compare this FileResource to another Resource.
       * @param another the other Resource against which to compare.
       * @return a negative integer, zero, or a positive integer as this FileResource
       *         is less than, equal to, or greater than the specified Resource.
       */
      @Override
      public int compareTo(Resource another) {
          if (isReference()) {
              return getRef().compareTo(another);
          }
          if (this.equals(another)) {
              return 0;
          }
          FileProvider otherFP = another.as(FileProvider.class);
          if (otherFP != null) {
              File f = getFile();
              if (f == null) {
                  return -1;
              }
              File of = otherFP.getFile();
              if (of == null) {
                  return 1;
              }
              int compareFiles = f.compareTo(of);
              return compareFiles != 0 ? compareFiles
                  : getName().compareTo(another.getName());
          }
          return super.compareTo(another);
      }
  
      /**
       * Compare another Object to this FileResource for equality.
       * @param another the other Object to compare.
       * @return true if another is a FileResource representing the same file.
       */
      @Override
      public boolean equals(Object another) {
          if (this == another) {
              return true;
          }
          if (isReference()) {
              return getRef().equals(another);
          }
          if (another == null || !(another.getClass().equals(getClass()))) {
              return false;
          }
          FileResource otherfr = (FileResource) another;
          return getFile() == null
              ? otherfr.getFile() == null
              : getFile().equals(otherfr.getFile()) && getName().equals(otherfr.getName());
      }
  
      /**
       * Get the hash code for this Resource.
       * @return hash code as int.
       */
      @Override
      public int hashCode() {
          if (isReference()) {
              return getRef().hashCode();
          }
          return MAGIC * (getFile() == null ? NULL_FILE : getFile().hashCode());
      }
  
      /**
       * Get the string representation of this Resource.
       * @return this FileResource formatted as a String.
       */
      @Override
      public String toString() {
          if (isReference()) {
              return getRef().toString();
          }
          if (file == null) {
              return "(unbound file resource)";
          }
          String absolutePath = file.getAbsolutePath();
          return FILE_UTILS.normalize(absolutePath).getAbsolutePath();
      }
  
      /**
       * Fulfill the ResourceCollection contract.
       * @return whether this Resource is a FileResource.
       */
      @Override
      public boolean isFilesystemOnly() {
          if (isReference()) {
              return getRef().isFilesystemOnly();
          }
          dieOnCircularReference();
          return true;
      }
  
      /**
       * Implement the Touchable interface.
       * @param modTime new last modification time.
       */
      @Override
      public void touch(long modTime) {
          if (isReference()) {
              getRef().touch(modTime);
              return;
          }
          if (!getNotNullFile().setLastModified(modTime)) {
              log("Failed to change file modification time", Project.MSG_WARN);
          }
      }
  
      /**
       * Get the file represented by this FileResource, ensuring it is not null.
       * @return the not-null File.
       * @throws BuildException if file is null.
       */
      protected File getNotNullFile() {
          if (getFile() == null) {
              throw new BuildException("file attribute is null!");
          }
          dieOnCircularReference();
          return getFile();
      }
  
      /**
       * Create a new resource that matches a relative or absolute path.
       * If the current instance has a compatible baseDir attribute, it is copied.
       * @param path relative/absolute path to a resource
       * @return a new resource of type FileResource
       * @throws BuildException if desired
       * @since Ant1.8
       */
      @Override
      public Resource getResource(String path) {
          File newfile = FILE_UTILS.resolveFile(getFile(), path);
          FileResource fileResource = new FileResource(newfile);
          if (FILE_UTILS.isLeadingPath(getBaseDir(), newfile)) {
              fileResource.setBaseDir(getBaseDir());
          }
          return fileResource;
      }
  
      @Override
      protected FileResource getRef() {
          return getCheckedRef(FileResource.class);
      }
  }
  