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.logging.log4j.core.pattern;
19
20 /**
21 * Modifies the output of a pattern converter for a specified minimum and maximum width and alignment.
22 */
23 public final class FormattingInfo {
24 /**
25 * Array of spaces.
26 */
27 private static final char[] SPACES = new char[] { ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ' };
28
29 /**
30 * Default instance.
31 */
32 private static final FormattingInfo DEFAULT = new FormattingInfo(false, 0, Integer.MAX_VALUE, true);
33
34 /**
35 * Minimum length.
36 */
37 private final int minLength;
38
39 /**
40 * Maximum length.
41 */
42 private final int maxLength;
43
44 /**
45 * Alignment.
46 */
47 private final boolean leftAlign;
48
49 /**
50 * Left vs. right-hand side truncation.
51 */
52 private final boolean leftTruncate;
53
54 /**
55 * Creates new instance.
56 *
57 * @param leftAlign
58 * left align if true.
59 * @param minLength
60 * minimum length.
61 * @param maxLength
62 * maximum length.
63 * @param leftTruncate
64 * truncates to the left if true
65 */
66 public FormattingInfo(final boolean leftAlign, final int minLength, final int maxLength, final boolean leftTruncate) {
67 this.leftAlign = leftAlign;
68 this.minLength = minLength;
69 this.maxLength = maxLength;
70 this.leftTruncate = leftTruncate;
71 }
72
73 /**
74 * Gets default instance.
75 *
76 * @return default instance.
77 */
78 public static FormattingInfo getDefault() {
79 return DEFAULT;
80 }
81
82 /**
83 * Determine if left aligned.
84 *
85 * @return true if left aligned.
86 */
87 public boolean isLeftAligned() {
88 return leftAlign;
89 }
90
91 /**
92 * Determine if left truncated.
93 *
94 * @return true if left truncated.
95 */
96 public boolean isLeftTruncate() {
97 return leftTruncate;
98 }
99
100 /**
101 * Get minimum length.
102 *
103 * @return minimum length.
104 */
105 public int getMinLength() {
106 return minLength;
107 }
108
109 /**
110 * Get maximum length.
111 *
112 * @return maximum length.
113 */
114 public int getMaxLength() {
115 return maxLength;
116 }
117
118 /**
119 * Adjust the content of the buffer based on the specified lengths and alignment.
120 *
121 * @param fieldStart
122 * start of field in buffer.
123 * @param buffer
124 * buffer to be modified.
125 */
126 public void format(final int fieldStart, final StringBuilder buffer) {
127 final int rawLength = buffer.length() - fieldStart;
128
129 if (rawLength > maxLength) {
130 if (leftTruncate) {
131 buffer.delete(fieldStart, buffer.length() - maxLength);
132 } else {
133 buffer.delete(fieldStart + maxLength, fieldStart + buffer.length());
134 }
135 } else if (rawLength < minLength) {
136 if (leftAlign) {
137 final int fieldEnd = buffer.length();
138 buffer.setLength(fieldStart + minLength);
139
140 for (int i = fieldEnd; i < buffer.length(); i++) {
141 buffer.setCharAt(i, ' ');
142 }
143 } else {
144 int padLength = minLength - rawLength;
145
146 for (; padLength > SPACES.length; padLength -= SPACES.length) {
147 buffer.insert(fieldStart, SPACES);
148 }
149
150 buffer.insert(fieldStart, SPACES, 0, padLength);
151 }
152 }
153 }
154
155 /**
156 * Returns a String suitable for debugging.
157 *
158 * @return a String suitable for debugging.
159 */
160 @Override
161 public String toString() {
162 final StringBuilder sb = new StringBuilder();
163 sb.append(super.toString());
164 sb.append("[leftAlign=");
165 sb.append(leftAlign);
166 sb.append(", maxLength=");
167 sb.append(maxLength);
168 sb.append(", minLength=");
169 sb.append(minLength);
170 sb.append(", leftTruncate=");
171 sb.append(leftTruncate);
172 sb.append(']');
173 return sb.toString();
174 }
175
176 }