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1
4 package com.tc.util.diff;
5
6 import org.apache.commons.lang.builder.EqualsBuilder;
7
8 import com.tc.util.Assert;
9 import com.tc.util.StandardStringifier;
10 import com.tc.util.Stringifier;
11
12 import java.lang.reflect.AccessibleObject  ;
13 import java.lang.reflect.Field ;
14 import java.lang.reflect.Modifier ;
15 import java.util.ArrayList ;
16 import java.util.Iterator ;
17 import java.util.List ;
18
19
23 public class DifferenceBuilder {
24
25 private static final Stringifier DEFAULT_STRINGIFIER = StandardStringifier.INSTANCE;
27
28 public static String describeDifferences(Differenceable a, Differenceable b) {
29 return describeDifferences(a, b, DEFAULT_STRINGIFIER);
30 }
31
32 public static String describeDifferences(Differenceable a, Differenceable b, Stringifier stringifier) {
33 Difference[] differences = getDifferencesAsArray(a, b);
34 if (differences.length == 0) return "";
35
36 StringBuffer descrip = new StringBuffer ();
37 descrip.append("differences are:\n");
38 for (int i = 0; i < differences.length; ++i) {
39 descrip.append(differences[i].toString());
40 descrip.append("\n");
41 }
42
43 return descrip.toString();
44 }
45
46 public static Iterator getDifferences(Differenceable a, Differenceable b, Stringifier stringifier) {
47 Assert.assertNotNull(a);
48 Assert.assertNotNull(b);
49
50 DifferenceContext context = DifferenceContext.createInitial(stringifier);
51
52 if (! (a.getClass().equals(b.getClass()))) {
53 context.addDifference(new BasicObjectDifference(context, a, b));
54 } else {
55 a.addDifferences(context, b);
56 }
57
58 return context.getDifferences();
59 }
60
61 public static Iterator getDifferences(Differenceable a, Differenceable b) {
62 return getDifferences(a, b, DEFAULT_STRINGIFIER);
63 }
64
65 public static Difference[] getDifferencesAsArray(Differenceable a, Differenceable b) {
66 return getDifferencesAsArray(a, b, DEFAULT_STRINGIFIER);
67 }
68
69 public static Difference[] getDifferencesAsArray(Differenceable a, Differenceable b, Stringifier stringifier) {
70 List out = new ArrayList ();
71 Iterator i = getDifferences(a, b, stringifier);
72 while (i.hasNext()) {
73 out.add(i.next());
74 }
75
76 return (Difference[]) out.toArray(new Difference[out.size()]);
77 }
78
79 private final DifferenceContext previous;
80
81 public DifferenceBuilder(DifferenceContext previous) {
82 Assert.assertNotNull(previous);
83
84 this.previous = previous;
85 }
86
87 public DifferenceBuilder reflectionDifference(Object a, Object b) {
88 Assert.assertNotNull(a);
89 Assert.assertNotNull(b);
90 Assert.eval(a instanceof Differenceable);
91 Assert.eval(b instanceof Differenceable);
92 Assert.eval(a.getClass().isInstance(b));
93
94 if (a == b) return this;
95
96 Field [] fields = a.getClass().getDeclaredFields();
97 AccessibleObject.setAccessible(fields, true);
98 for (int i = 0; i < fields.length; ++i) {
99 Field f = fields[i];
100 if (!Modifier.isStatic(f.getModifiers())) {
101 try {
102 doReflectiveAppend(f.getName(), f.get(a), f.get(b), f.getType());
103 } catch (IllegalAccessException iae) {
104 throw Assert.failure("This should be impossible", iae);
106 }
107 }
108 }
109
110 return this;
111 }
112
113 private void doReflectiveAppend(String context, Object a, Object b, Class c) {
114 if (c.isPrimitive()) {
115 if (c.equals(Boolean.TYPE)) append(context, ((Boolean ) a).booleanValue(), ((Boolean ) b).booleanValue());
116 else if (c.equals(Character.TYPE)) append(context, ((Character ) a).charValue(), ((Character ) b).charValue());
117 else if (c.equals(Byte.TYPE)) append(context, ((Byte ) a).byteValue(), ((Byte ) b).byteValue());
118 else if (c.equals(Short.TYPE)) append(context, ((Short ) a).shortValue(), ((Short ) b).shortValue());
119 else if (c.equals(Integer.TYPE)) append(context, ((Integer ) a).intValue(), ((Integer ) b).intValue());
120 else if (c.equals(Long.TYPE)) append(context, ((Long ) a).longValue(), ((Long ) b).longValue());
121 else if (c.equals(Float.TYPE)) append(context, ((Float ) a).floatValue(), ((Float ) b).floatValue());
122 else if (c.equals(Double.TYPE)) append(context, ((Double ) a).doubleValue(), ((Double ) b).doubleValue());
123 else throw Assert.failure("Unknown primitive type " + c);
124 } else {
125 append(context, a, b);
126 }
127 }
128
129 public DifferenceBuilder append(String context, boolean a, boolean b) {
130 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
131 return this;
132 }
133
134 public DifferenceBuilder append(String context, char a, char b) {
135 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
136 return this;
137 }
138
139 public DifferenceBuilder append(String context, byte a, byte b) {
140 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
141 return this;
142 }
143
144 public DifferenceBuilder append(String context, short a, short b) {
145 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
146 return this;
147 }
148
149 public DifferenceBuilder append(String context, int a, int b) {
150 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
151 return this;
152 }
153
154 public DifferenceBuilder append(String context, long a, long b) {
155 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
156 return this;
157 }
158
159 public DifferenceBuilder append(String context, float a, float b) {
160 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
161 return this;
162 }
163
164 public DifferenceBuilder append(String context, double a, double b) {
165 if (a != b) add(new PrimitiveDifference(this.previous.sub(context), a, b));
166 return this;
167 }
168
169 public DifferenceBuilder append(String context, Object a, Object b) {
170 if (a != null && b != null) {
171 if ((a instanceof Differenceable) && (b instanceof Differenceable) &&
172 (a.getClass().equals(b.getClass()))) {
173 handleDifferenceables(context, a, b);
174 } else if (a.getClass().isArray() && b.getClass().isArray()) {
175 handleArrays(context, a, b);
176 } else if (!(a.equals(b))) {
177 add(new BasicObjectDifference(this.previous.sub(context), a, b));
178 }
179 } else if (a != null || b != null) {
180 add(new BasicObjectDifference(this.previous.sub(context), a, b));
181 }
182
183 return this;
184 }
185
186 private void handleArrays(String context, Object a, Object b) {
187 if ((a.getClass().getComponentType().isPrimitive() || b.getClass().getComponentType().isPrimitive())
188 && (!a.getClass().getComponentType().equals(b.getClass().getComponentType()))) {
189 add(new BasicObjectDifference(this.previous.sub(context), a, b));
190 }
191
192 if (a.getClass().getComponentType().isPrimitive()) {
193 if (a instanceof boolean[]) {
194 handleArrays(context, (boolean[]) a, (boolean[]) b);
195 } else if (a instanceof char[]) {
196 handleArrays(context, (char[]) a, (char[]) b);
197 } else if (a instanceof byte[]) {
198 handleArrays(context, (byte[]) a, (byte[]) b);
199 } else if (a instanceof short[]) {
200 handleArrays(context, (short[]) a, (short[]) b);
201 } else if (a instanceof int[]) {
202 handleArrays(context, (int[]) a, (int[]) b);
203 } else if (a instanceof long[]) {
204 handleArrays(context, (long[]) a, (long[]) b);
205 } else if (a instanceof float[]) {
206 handleArrays(context, (float[]) a, (float[]) b);
207 } else if (a instanceof double[]) {
208 handleArrays(context, (double[]) a, (double[]) b);
209 } else {
210 throw Assert.failure("Unknown primitive type " + a.getClass().getComponentType());
211 }
212 } else {
213 handleArrays(context, (Object []) a, (Object []) b);
214 }
215 }
216
217 private void handleArrays(String context, boolean[] a, boolean[] b) {
218 if (a.length != b.length) {
219 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
220 } else {
221 for (int i = 0; i < a.length; ++i) {
222 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
223 }
224 }
225 }
226
227 private void handleArrays(String context, char[] a, char[] b) {
228 if (a.length != b.length) {
229 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
230 } else {
231 for (int i = 0; i < a.length; ++i) {
232 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
233 }
234 }
235 }
236
237 private void handleArrays(String context, byte[] a, byte[] b) {
238 if (a.length != b.length) {
239 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
240 } else {
241 for (int i = 0; i < a.length; ++i) {
242 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
243 }
244 }
245 }
246
247 private void handleArrays(String context, short[] a, short[] b) {
248 if (a.length != b.length) {
249 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
250 } else {
251 for (int i = 0; i < a.length; ++i) {
252 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
253 }
254 }
255 }
256
257 private void handleArrays(String context, int[] a, int[] b) {
258 if (a.length != b.length) {
259 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
260 } else {
261 for (int i = 0; i < a.length; ++i) {
262 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
263 }
264 }
265 }
266
267 private void handleArrays(String context, long[] a, long[] b) {
268 if (a.length != b.length) {
269 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
270 } else {
271 for (int i = 0; i < a.length; ++i) {
272 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
273 }
274 }
275 }
276
277 private void handleArrays(String context, float[] a, float[] b) {
278 if (a.length != b.length) {
279 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
280 } else {
281 for (int i = 0; i < a.length; ++i) {
282 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
283 }
284 }
285 }
286
287 private void handleArrays(String context, double[] a, double[] b) {
288 if (a.length != b.length) {
289 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
290 } else {
291 for (int i = 0; i < a.length; ++i) {
292 if (a[i] != b[i]) add(new PrimitiveDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
293 }
294 }
295 }
296
297 private void handleArrays(String context, Object [] a, Object [] b) {
298 if (a.length != b.length) {
299 add(new PrimitiveDifference(this.previous.sub(context + ".length"), a.length, b.length));
300 } else {
301 for (int i = 0; i < a.length; ++i) {
302 if ((a[i] == null) != (b[i] == null)) {
303 add(new BasicObjectDifference(this.previous.sub(context + "[" + i + "]"), a[i], b[i]));
304 } else if (a[i] != null) {
305 this.append(context + "[" + i + "]", a[i], b[i]);
306 }
307 }
308 }
309 }
310
311 private void handleDifferenceables(String context, Object a, Object b) {
312 int preSize = countDifferences();
313 ((Differenceable) a).addDifferences(this.previous.sub(context), b);
314 boolean hadDifferences = (countDifferences() - preSize) > 0;
315
316 boolean equals = a.equals(b);
317 Assert.eval("differences added (" + hadDifferences + ") is not same as equals(" + equals + ")",
318 hadDifferences != equals);
319 }
320
321 private void add(Difference difference) {
322 difference.where().addDifference(difference);
323 }
324
325 private int countDifferences() {
326 return this.previous.countDifferences();
327 }
328
329 } |
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