1/* 2 * Copyright (C) 2012 The Android Open Source Project 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, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package com.android.internal.util; 18 19import java.io.PrintWriter; 20import java.io.Writer; 21 22/** 23 * Lightweight wrapper around {@link PrintWriter} that automatically indents 24 * newlines based on internal state. Delays writing indent until first actual 25 * write on a newline, enabling indent modification after newline. 26 */ 27public class IndentingPrintWriter extends PrintWriter { 28 private final String mIndent; 29 30 private StringBuilder mBuilder = new StringBuilder(); 31 private String mCurrent = new String(); 32 private boolean mEmptyLine = true; 33 34 public IndentingPrintWriter(Writer writer, String indent) { 35 super(writer); 36 mIndent = indent; 37 } 38 39 public void increaseIndent() { 40 mBuilder.append(mIndent); 41 mCurrent = mBuilder.toString(); 42 } 43 44 public void decreaseIndent() { 45 mBuilder.delete(0, mIndent.length()); 46 mCurrent = mBuilder.toString(); 47 } 48 49 public void printPair(String key, Object value) { 50 print(key + "=" + String.valueOf(value) + " "); 51 } 52 53 @Override 54 public void println() { 55 super.println(); 56 mEmptyLine = true; 57 } 58 59 @Override 60 public void write(char[] buf, int offset, int count) { 61 if (mEmptyLine) { 62 mEmptyLine = false; 63 super.print(mCurrent); 64 } 65 super.write(buf, offset, count); 66 } 67} 68