content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed 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
   *
   *      http://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 com.alibaba.csp.sentinel.eagleeye;
  
  import java.time.Instant;
  import java.time.ZoneId;
  import java.time.format.DateTimeFormatter;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.TimeUnit;
  
  final class EagleEyeCoreUtils {
  
      public static final String EMPTY_STRING = "";
      public static final String NEWLINE = "\r\n";
  
      public static final String[] EMPTY_STRING_ARRAY = new String[0];
  
      public static boolean isBlank(String str) {
          int strLen;
          if (str == null || (strLen = str.length()) == 0) {
              return true;
          }
          for (int i = 0; i < strLen; i++) {
              if ((!Character.isWhitespace(str.charAt(i)))) {
                  return false;
              }
          }
          return true;
      }
  
      public static String checkNotNullEmpty(String value, String name) throws IllegalArgumentException {
          if (isBlank(value)) {
              throw new IllegalArgumentException(name + " is null or empty");
          }
          return value;
      }
  
      public static <T> T checkNotNull(T value, String name) throws IllegalArgumentException {
          if (value == null) {
              throw new IllegalArgumentException(name + " is null");
          }
          return value;
      }
  
      public static <T> T defaultIfNull(T value, T defaultValue) {
          return (value == null) ? defaultValue : value;
      }
  
      public static boolean isNotBlank(String str) {
          return !isBlank(str);
      }
  
      public static boolean isNotEmpty(String str) {
          return str != null && str.length() > 0;
      }
  
      public static String trim(String str) {
          return str == null ? null : str.trim();
      }
  
      public static String[] split(String str, char separatorChar) {
          return splitWorker(str, separatorChar, false);
      }
  
      private static String[] splitWorker(String str, char separatorChar, boolean preserveAllTokens) {
          if (str == null) {
              return null;
          }
          int len = str.length();
          if (len == 0) {
              return EMPTY_STRING_ARRAY;
          }
          List<String> list = new ArrayList<String>();
          int i = 0, start = 0;
          boolean match = false;
          boolean lastMatch = false;
          while (i < len) {
              if (str.charAt(i) == separatorChar) {
                  if (match || preserveAllTokens) {
                      list.add(str.substring(start, i));
                      match = false;
                      lastMatch = true;
                  }
                  start = ++i;
                  continue;
              }
              lastMatch = false;
              match = true;
              i++;
          }
          if (match || (preserveAllTokens && lastMatch)) {
              list.add(str.substring(start, i));
          }
          return list.toArray(new String[list.size()]);
      }
  
      public static StringBuilder appendWithBlankCheck(String str, String defaultValue, StringBuilder appender) {
          if (isNotBlank(str)) {
              appender.append(str);
          } else {
              appender.append(defaultValue);
          }
          return appender;
      }
  
      public static StringBuilder appendWithNullCheck(Object obj, String defaultValue, StringBuilder appender) {
          if (obj != null) {
              appender.append(obj.toString());
          } else {
              appender.append(defaultValue);
          }
          return appender;
      }
  
      public static StringBuilder appendLog(String str, StringBuilder appender, char delimiter) {
          if (str != null) {
              int len = str.length();
              appender.ensureCapacity(appender.length() + len);
              for (int i = 0; i < len; i++) {
                  char c = str.charAt(i);
                  if (c == '\n' || c == '\r' || c == delimiter) {
                      c = ' ';
                  }
                  appender.append(c);
              }
          }
          return appender;
      }
  
      private static final DateTimeFormatter dateFmt = DateTimeFormatter
              .ofPattern("yyyy-MM-dd HH:mm:ss.SSS")
              .withZone(ZoneId.systemDefault());
  
      public static String formatTime(long timestamp) {
          return dateFmt.format(Instant.ofEpochMilli(timestamp));
      }
  
      public static String getSystemProperty(String key) {
          try {
              return System.getProperty(key);
          } catch (Throwable t) {
              return null;
          }
      }
  
      public static long getSystemPropertyForLong(String key, long defaultValue) {
          try {
              return Long.parseLong(System.getProperty(key));
          } catch (Throwable t) {
              return defaultValue;
          }
      }
  
      public static boolean isHexNumeric(char ch) {
          return (ch >= 'a' && ch <= 'f') || (ch >= '0' && ch <= '9');
      }
  
      public static boolean isNumeric(char ch) {
          return ch >= '0' && ch <= '9';
      }
  
      public static void shutdownThreadPool(ExecutorService pool, long awaitTimeMillis) {
          try {
              pool.shutdown();
  
              boolean done = false;
              if (awaitTimeMillis > 0) {
                  try {
                      done = pool.awaitTermination(awaitTimeMillis, TimeUnit.MILLISECONDS);
                  } catch (Exception e) {
                  }
              }
  
              if (!done) {
                  pool.shutdownNow();
              }
          } catch (Exception e) {
              // quietly
          }
      }
  
  }
  