1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
/*
* Copyright (C) 2016 The Android Open Source Project
*
* 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.android.voicemail.impl.utils;
import java.io.PrintWriter;
import java.io.Writer;
import java.util.Arrays;
/**
* Lightweight wrapper around {@link PrintWriter} that automatically indents newlines based on
* internal state. It also automatically wraps long lines based on given line length.
*
* <p>Delays writing indent until first actual write on a newline, enabling indent modification
* after newline.
*/
public class IndentingPrintWriter extends PrintWriter {
private final String mSingleIndent;
private final int mWrapLength;
/** Mutable version of current indent */
private StringBuilder mIndentBuilder = new StringBuilder();
/** Cache of current {@link #mIndentBuilder} value */
private char[] mCurrentIndent;
/** Length of current line being built, excluding any indent */
private int mCurrentLength;
/**
* Flag indicating if we're currently sitting on an empty line, and that next write should be
* prefixed with the current indent.
*/
private boolean mEmptyLine = true;
private char[] mSingleChar = new char[1];
public IndentingPrintWriter(Writer writer, String singleIndent) {
this(writer, singleIndent, -1);
}
public IndentingPrintWriter(Writer writer, String singleIndent, int wrapLength) {
super(writer);
mSingleIndent = singleIndent;
mWrapLength = wrapLength;
}
public void increaseIndent() {
mIndentBuilder.append(mSingleIndent);
mCurrentIndent = null;
}
public void decreaseIndent() {
mIndentBuilder.delete(0, mSingleIndent.length());
mCurrentIndent = null;
}
public void printPair(String key, Object value) {
print(key + "=" + String.valueOf(value) + " ");
}
public void printPair(String key, Object[] value) {
print(key + "=" + Arrays.toString(value) + " ");
}
public void printHexPair(String key, int value) {
print(key + "=0x" + Integer.toHexString(value) + " ");
}
@Override
public void println() {
write('\n');
}
@Override
public void write(int c) {
mSingleChar[0] = (char) c;
write(mSingleChar, 0, 1);
}
@Override
public void write(String s, int off, int len) {
final char[] buf = new char[len];
s.getChars(off, len - off, buf, 0);
write(buf, 0, len);
}
@Override
public void write(char[] buf, int offset, int count) {
final int indentLength = mIndentBuilder.length();
final int bufferEnd = offset + count;
int lineStart = offset;
int lineEnd = offset;
// March through incoming buffer looking for newlines
while (lineEnd < bufferEnd) {
char ch = buf[lineEnd++];
mCurrentLength++;
if (ch == '\n') {
maybeWriteIndent();
super.write(buf, lineStart, lineEnd - lineStart);
lineStart = lineEnd;
mEmptyLine = true;
mCurrentLength = 0;
}
// Wrap if we've pushed beyond line length
if (mWrapLength > 0 && mCurrentLength >= mWrapLength - indentLength) {
if (!mEmptyLine) {
// Give ourselves a fresh line to work with
super.write('\n');
mEmptyLine = true;
mCurrentLength = lineEnd - lineStart;
} else {
// We need more than a dedicated line, slice it hard
maybeWriteIndent();
super.write(buf, lineStart, lineEnd - lineStart);
super.write('\n');
mEmptyLine = true;
lineStart = lineEnd;
mCurrentLength = 0;
}
}
}
if (lineStart != lineEnd) {
maybeWriteIndent();
super.write(buf, lineStart, lineEnd - lineStart);
}
}
private void maybeWriteIndent() {
if (mEmptyLine) {
mEmptyLine = false;
if (mIndentBuilder.length() != 0) {
if (mCurrentIndent == null) {
mCurrentIndent = mIndentBuilder.toString().toCharArray();
}
super.write(mCurrentIndent, 0, mCurrentIndent.length);
}
}
}
}
|
