1
14 package ch.qos.logback.classic.spi;
15
16 import ch.qos.logback.core.CoreConstants;
17
18
24 public class ThrowableProxyUtil {
25
26 public static final int REGULAR_EXCEPTION_INDENT = 1;
27 public static final int SUPPRESSED_EXCEPTION_INDENT = 1;
28 private static final int BUILDER_CAPACITY = 2048;
29
30 public static void build(ThrowableProxy nestedTP, Throwable nestedThrowable, ThrowableProxy parentTP) {
31
32 StackTraceElement[] nestedSTE = nestedThrowable.getStackTrace();
33
34 int commonFramesCount = -1;
35 if (parentTP != null) {
36 commonFramesCount = findNumberOfCommonFrames(nestedSTE, parentTP.getStackTraceElementProxyArray());
37 }
38
39 nestedTP.commonFrames = commonFramesCount;
40 nestedTP.stackTraceElementProxyArray = steArrayToStepArray(nestedSTE);
41 }
42
43 static StackTraceElementProxy[] steArrayToStepArray(StackTraceElement[] stea) {
44 if (stea == null) {
45 return new StackTraceElementProxy[0];
46 }
47 StackTraceElementProxy[] stepa = new StackTraceElementProxy[stea.length];
48 for (int i = 0; i < stepa.length; i++) {
49 stepa[i] = new StackTraceElementProxy(stea[i]);
50 }
51 return stepa;
52 }
53
54 static int findNumberOfCommonFrames(StackTraceElement[] steArray, StackTraceElementProxy[] parentSTEPArray) {
55 if (parentSTEPArray == null || steArray == null) {
56 return 0;
57 }
58
59 int steIndex = steArray.length - 1;
60 int parentIndex = parentSTEPArray.length - 1;
61 int count = 0;
62 while (steIndex >= 0 && parentIndex >= 0) {
63 StackTraceElement ste = steArray[steIndex];
64 StackTraceElement otherSte = parentSTEPArray[parentIndex].ste;
65 if (ste.equals(otherSte)) {
66 count++;
67 } else {
68 break;
69 }
70 steIndex--;
71 parentIndex--;
72 }
73 return count;
74 }
75
76 public static String asString(IThrowableProxy tp) {
77 StringBuilder sb = new StringBuilder(BUILDER_CAPACITY);
78
79 recursiveAppend(sb, null, REGULAR_EXCEPTION_INDENT, tp);
80
81 return sb.toString();
82 }
83
84 private static void recursiveAppend(StringBuilder sb, String prefix, int indent, IThrowableProxy tp) {
85 if (tp == null)
86 return;
87 subjoinFirstLine(sb, prefix, indent, tp);
88 sb.append(CoreConstants.LINE_SEPARATOR);
89 subjoinSTEPArray(sb, indent, tp);
90 IThrowableProxy[] suppressed = tp.getSuppressed();
91 if (suppressed != null) {
92 for (IThrowableProxy current : suppressed) {
93 recursiveAppend(sb, CoreConstants.SUPPRESSED, indent + SUPPRESSED_EXCEPTION_INDENT, current);
94 }
95 }
96 recursiveAppend(sb, CoreConstants.CAUSED_BY, indent, tp.getCause());
97 }
98
99 public static void indent(StringBuilder buf, int indent) {
100 for (int j = 0; j < indent; j++) {
101 buf.append(CoreConstants.TAB);
102 }
103 }
104
105 private static void subjoinFirstLine(StringBuilder buf, String prefix, int indent, IThrowableProxy tp) {
106 indent(buf, indent - 1);
107 if (prefix != null) {
108 buf.append(prefix);
109 }
110 subjoinExceptionMessage(buf, tp);
111 }
112
113 public static void subjoinPackagingData(StringBuilder builder, StackTraceElementProxy step) {
114 if (step != null) {
115 ClassPackagingData cpd = step.getClassPackagingData();
116 if (cpd != null) {
117 if (!cpd.isExact()) {
118 builder.append(" ~[");
119 } else {
120 builder.append(" [");
121 }
122
123 builder.append(cpd.getCodeLocation()).append(':').append(cpd.getVersion()).append(']');
124 }
125 }
126 }
127
128 public static void subjoinSTEP(StringBuilder sb, StackTraceElementProxy step) {
129 sb.append(step.toString());
130 subjoinPackagingData(sb, step);
131 }
132
133
138 public static void subjoinSTEPArray(StringBuilder sb, IThrowableProxy tp) {
139
140 subjoinSTEPArray(sb, REGULAR_EXCEPTION_INDENT, tp);
141 }
142
143
148 public static void subjoinSTEPArray(StringBuilder sb, int indentLevel, IThrowableProxy tp) {
149 StackTraceElementProxy[] stepArray = tp.getStackTraceElementProxyArray();
150 int commonFrames = tp.getCommonFrames();
151
152 for (int i = 0; i < stepArray.length - commonFrames; i++) {
153 StackTraceElementProxy step = stepArray[i];
154 indent(sb, indentLevel);
155 subjoinSTEP(sb, step);
156 sb.append(CoreConstants.LINE_SEPARATOR);
157 }
158
159 if (commonFrames > 0) {
160 indent(sb, indentLevel);
161 sb.append("... ").append(commonFrames).append(" common frames omitted").append(CoreConstants.LINE_SEPARATOR);
162 }
163
164 }
165
166 public static void subjoinFirstLine(StringBuilder buf, IThrowableProxy tp) {
167 int commonFrames = tp.getCommonFrames();
168 if (commonFrames > 0) {
169 buf.append(CoreConstants.CAUSED_BY);
170 }
171 subjoinExceptionMessage(buf, tp);
172 }
173
174 public static void subjoinFirstLineRootCauseFirst(StringBuilder buf, IThrowableProxy tp) {
175 if (tp.getCause() != null) {
176 buf.append(CoreConstants.WRAPPED_BY);
177 }
178 subjoinExceptionMessage(buf, tp);
179 }
180
181 private static void subjoinExceptionMessage(StringBuilder buf, IThrowableProxy tp) {
182 buf.append(tp.getClassName()).append(": ").append(tp.getMessage());
183 }
184 }
185