ceph/src/arrow/java/memory/memory-core/src/main/java/org/apache/arrow/memory/util/StackTrace.java

   1 /*
   2  * Licensed to the Apache Software Foundation (ASF) under one or more
   3  * contributor license agreements.  See the NOTICE file distributed with
   4  * this work for additional information regarding copyright ownership.
   5  * The ASF licenses this file to You under the Apache License, Version 2.0
   6  * (the "License"); you may not use this file except in compliance with
   7  * the License.  You may obtain a copy of the License at
   8  *
   9  *    http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 package org.apache.arrow.memory.util;
  19
  20 import java.util.Arrays;
  21
  22 /**
  23  * Convenient way of obtaining and manipulating stack traces for debugging.
  24  */
  25 public class StackTrace {
  26
  27   private final StackTraceElement[] stackTraceElements;
  28
  29   /**
  30    * Constructor. Captures the current stack trace.
  31    */
  32   public StackTrace() {
  33     // skip over the first element so that we don't include this constructor call
  34     final StackTraceElement[] stack = Thread.currentThread().getStackTrace();
  35     stackTraceElements = Arrays.copyOfRange(stack, 1, stack.length - 1);
  36   }
  37
  38   /**
  39    * Write the stack trace to a StringBuilder.
  40    *
  41    * @param sb     where to write it
  42    * @param indent how many double spaces to indent each line
  43    */
  44   public void writeToBuilder(final StringBuilder sb, final int indent) {
  45     // create the indentation string
  46     final char[] indentation = new char[indent * 2];
  47     Arrays.fill(indentation, ' ');
  48
  49     // write the stack trace in standard Java format
  50     for (StackTraceElement ste : stackTraceElements) {
  51       sb.append(indentation)
  52           .append("at ")
  53           .append(ste.getClassName())
  54           .append('.')
  55           .append(ste.getMethodName())
  56           .append('(')
  57           .append(ste.getFileName())
  58           .append(':')
  59           .append(Integer.toString(ste.getLineNumber()))
  60           .append(")\n");
  61     }
  62   }
  63
  64   @Override
  65   public String toString() {
  66     final StringBuilder sb = new StringBuilder();
  67     writeToBuilder(sb, 0);
  68     return sb.toString();
  69   }
  70 }