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1
2
12 package com.versant.core.jdo.tools.enhancer;
13
14 import com.versant.core.jdo.tools.enhancer.utils.*;
15
16 import java.util.*;
17 import java.io.*;
18 import java.net.URL  ;
19
20 import com.versant.lib.bcel.classfile.*;
21 import com.versant.lib.bcel.generic.*;
22 import com.versant.lib.bcel.Constants;
23 import com.versant.lib.bcel.*;
24
27 public class FieldRefEnhancer {
28 private ClassLoader loader;
29 private HashMap fieldToEnhanceMap;
30 private ClassGen classGen;
31 private ConstantPoolGen constantPoolGen;
32 private InstructionFactory instructionFactory;
33 private File outputDir;
34 private ArrayList pcList = new ArrayList();
35 private boolean hasChanges;
36 private static final String GET_FIELD = com.versant.lib.bcel.generic.GETFIELD.class.getName();
37 private static final String PUT_FIELD = com.versant.lib.bcel.generic.PUTFIELD.class.getName();
38 private static final String A_LOAD = com.versant.lib.bcel.generic.ALOAD.class.getName();
39 private static final String D_U_P = com.versant.lib.bcel.generic.DUP.class.getName();
40 private int aware;
41 private String fileSeparator;
42 private char charfileSeparator;
43 private File currentOutputFile;
44
45
46 public FieldRefEnhancer(File outputDir,ClassLoader loader) {
47 this.outputDir = outputDir;
48 this.loader = loader;
49 fileSeparator = System.getProperty("file.separator");
50 charfileSeparator = fileSeparator.charAt(0);
51 }
52
53 public void setFieldsToEnhanceMap(HashMap map){
54 fieldToEnhanceMap = map;
55 }
56
57 public int getAwareNum(){
58 return aware;
59 }
60 public void setPersistentCapable(String pcClassName){
61 pcList.add(pcClassName);
62 }
63
64 public void enhance(Set scopeFiles){
65 if (fieldToEnhanceMap.isEmpty())return;
66 Iterator iter = scopeFiles.iterator();
67 while (iter.hasNext()){
68 String fileName = (String )iter.next();
69 try {
70 hasChanges = false;
71 JavaClass javaClass = getJavaClass(fileName);
72 classGen = new ClassGen(javaClass);
73 if (!pcList.contains(classGen.getClassName())) {
74 constantPoolGen = classGen.getConstantPool();
76 instructionFactory = new InstructionFactory(constantPoolGen);
78 swapGetterAndSetter();
79 if (hasChanges){
80 dumpClass();
81 aware++;
82 System.out.println("Persistent Aware = " + classGen.getClassName());
83 }
84 }
85 } catch (Exception e){
86 e.printStackTrace(); }
88 }
89 }
90
91
92 private JavaClass getJavaClass(String className) throws IOException {
93 InputStream inputStream = loader.getResourceAsStream(className);
94 if (inputStream == null) {
95 if (inputStream == null) {
96 throw new javax.jdo.JDOFatalUserException("Class not found: " + className);
97 }
98 }
99 ClassParser parser = new ClassParser(inputStream, className);
100 return parser.parse();
101 }
102
103 private void dumpClass() throws VerifyException {
104 String fileName = classGen.getClassName().replace('.', charfileSeparator) + ".class";
105 File dumpFile;
106 if (outputDir != null) {
107 dumpFile = new File(outputDir, fileName);
108 } else {
109 URL currentFileURL = loader.getResource(fileName);
110 if (currentFileURL.toString().startsWith("jar:")) {
111 throw new javax.jdo.JDOFatalUserException("Can not write file " + fileName + " into a jar. Please specify a output directory.");
112 }
113 currentOutputFile = new File(currentFileURL.getFile());
114 dumpFile = currentOutputFile;
115 }
116 try {
117 classGen.getJavaClass().dump(dumpFile);
118 } catch (IOException e) {
119 throw new VerifyException(e);
120 }
121
122 }
123
124
125 private void swapGetterAndSetter() {
126
127 Method[] methods = classGen.getMethods();
129 for (int i = 0; i < methods.length; i++) {
130 Method m = methods[i];
131
132 if (m.isNative() || m.isAbstract()) {
135 continue;
136 }
137 if (m.getName().startsWith("jdo") || m.getName().startsWith("<c")) {
139 continue;
140 }
141
142 boolean changed = false;
143
144 MethodGen mg = new MethodGen(m, classGen.getClassName(), constantPoolGen);
145
146 InstructionList il = mg.getInstructionList();
148
149 InstructionHandle ih = il.getStart();
151 while (ih != null) {
152 Instruction ins = ih.getInstruction();
153 if (ins.getClass().getName().equals(GET_FIELD)) { GETFIELD is = (GETFIELD) ins;
155 if (!is.getFieldName(constantPoolGen).startsWith("jdo")) {
156 String key = is.getClassName(constantPoolGen) + "|" + is.getFieldName(constantPoolGen);
157 if (fieldToEnhanceMap.containsKey(key)) {
158 SwapFieldHelper helper = (SwapFieldHelper) fieldToEnhanceMap.get(key);
159 ih.setInstruction(instructionFactory.createInvoke(
161 helper.className,
162 helper.jdoGetName,
163 helper.type,
164 new Type[]{
165 new ObjectType(helper.className)
166 },
167 Constants.INVOKESTATIC));
168 il.setPositions();
169 il.update();
170
171 changed = true;
172 InstructionHandle prevIhDUP = ih.getPrev();
173 Instruction iffyDup = prevIhDUP.getInstruction();
174 if (iffyDup.getClass().getName().equals(D_U_P)) { ih = ih.getPrev();
176 InstructionHandle prevIhALOAD = ih.getPrev();
177 Instruction iffyAload = prevIhALOAD.getInstruction();
178 if (iffyAload.getClass().getName().equals(A_LOAD)) { ALOAD aLoad = (ALOAD) iffyAload;
180 ih.setInstruction(aLoad); il.setPositions();
182 il.update();
183 } else {
184 ih = ih.getNext();
185 }
186 }
187 }
188 }
189 } else if (ins.getClass().getName().equals(PUT_FIELD)) {
190 PUTFIELD is = (PUTFIELD) ins;
191 if (!is.getFieldName(constantPoolGen).startsWith("jdo")) {
192 String key = is.getClassName(constantPoolGen) + "|" + is.getFieldName(constantPoolGen);
193 if (fieldToEnhanceMap.containsKey(key)) {
194 SwapFieldHelper helper = (SwapFieldHelper) fieldToEnhanceMap.get(key);
195 ih.setInstruction(instructionFactory.createInvoke(
197 helper.className,
198 helper.jdoSetName,
199 Type.VOID,
200 new Type[]{
201 new ObjectType(helper.className),
202 helper.type
203 },
204 Constants.INVOKESTATIC));
205 il.setPositions();
206 il.update();
207 changed = true;
208 }
209 }
210 }
211 ih = ih.getNext();
213 }
214 if (changed) {
215 hasChanges = true;
216 il.setPositions();
217 il.update();
218 mg.setMaxLocals();
219 mg.setMaxStack();
220 Method method = mg.getMethod();
221 classGen.replaceMethod(m, method);
222 }
223 }
224 }
225 }
226 |
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