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1   /*
2    * Copyright 2012-2017 CodeLibs Project and the Others.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *     http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
13   * either express or implied. See the License for the specific language
14   * governing permissions and limitations under the License.
15   */
16  package org.codelibs.fess.util;
17  
18  import org.apache.commons.io.FileUtils;
19  import org.codelibs.core.lang.StringUtil;
20  
21  public final class MemoryUtil {
22      private MemoryUtil() {
23      }
24  
25      public static String getMemoryUsageLog() {
26          final Runtime runtime = Runtime.getRuntime();
27          final long freeBytes = runtime.freeMemory();
28          final long maxBytes = runtime.maxMemory();
29          final long totalBytes = runtime.totalMemory();
30          final long usedBytes = totalBytes - freeBytes;
31          return "Mem:{used " + byteCountToDisplaySize(usedBytes) + ", heap " + byteCountToDisplaySize(totalBytes) + ", max "
32                  + byteCountToDisplaySize(maxBytes) + "}";
33      }
34  
35      public static String byteCountToDisplaySize(final long size) {
36          return FileUtils.byteCountToDisplaySize(size).replace(" ", StringUtil.EMPTY);
37      }
38  
39      public static long getUsedMemory() {
40          final Runtime runtime = Runtime.getRuntime();
41          final long freeBytes = runtime.freeMemory();
42          final long totalBytes = runtime.totalMemory();
43          return totalBytes - freeBytes;
44      }
45  }