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30
31 package oracle.toplink.libraries.asm.attrs;
32
33 import java.util.ArrayList  ;
34 import java.util.Iterator ;
35 import java.util.List ;
36 import java.util.Set ;
37
38 import oracle.toplink.libraries.asm.ByteVector;
39 import oracle.toplink.libraries.asm.ClassReader;
40 import oracle.toplink.libraries.asm.ClassWriter;
41 import oracle.toplink.libraries.asm.Label;
42
43
44
56
57 public class StackMapFrame {
58
59 public Label label;
60
61 public List locals = new ArrayList ();
62
63 public List stack = new ArrayList ();
64
65 public int read (ClassReader cr,
66 int off, char[] buf, int codeOff, Label[] labels) {
67 int n = cr.readUnsignedShort(off);
68 off += 2;
69 if (labels[n] == null) {
70 labels[n] = new Label();
71 }
72 label = labels[n];
73 off = readTypeInfo(cr, off, locals, labels, buf,
74 cr.readUnsignedShort(codeOff + 2)); off = readTypeInfo(cr, off, stack, labels, buf,
76 cr.readUnsignedShort(codeOff)); return off;
78 }
79
80 public void write (ClassWriter cw,
81 int maxStack, int maxLocals, ByteVector bv) {
82 bv.putShort(label.getOffset());
83 writeTypeInfo(bv, cw, locals, maxLocals);
84 writeTypeInfo(bv, cw, stack, maxStack);
85 }
86
87 public void getLabels (Set labels) {
88 labels.add(label);
89 getTypeInfoLabels(labels, locals);
90 getTypeInfoLabels(labels, stack);
91 }
92
93 private void getTypeInfoLabels (Set labels, List info) {
94 for (Iterator it = info.iterator(); it.hasNext();) {
95 StackMapType typeInfo = (StackMapType)it.next();
96 if (typeInfo.getType() == StackMapType.ITEM_Uninitialized) {
97 labels.add(typeInfo.getLabel());
98 }
99 }
100 }
101
102 private int readTypeInfo (ClassReader cr, int off,
103 List info, Label[] labels, char[] buf, int max) {
104 int n = 0;
105 if (max > StackMapAttribute.MAX_SIZE) {
106 n = cr.readInt(off);
107 off += 4;
108 } else {
109 n = cr.readUnsignedShort(off);
110 off += 2;
111 }
112 for (int j = 0; j < n; j++) {
113 int itemType = cr.readByte(off++);
114 StackMapType typeInfo = StackMapType.getTypeInfo(itemType);
115 info.add(typeInfo);
116 switch (itemType) {
117
122 case StackMapType.ITEM_Object: typeInfo.setObject(cr.readClass(off, buf));
124 off += 2;
125 break;
126
127 case StackMapType.ITEM_Uninitialized: int o = cr.readUnsignedShort(off);
129 off += 2;
130 if (labels[o] == null) {
131 labels[o] = new Label();
132 }
133 typeInfo.setLabel(labels[o]);
134 break;
135 }
136 }
137 return off;
138 }
139
140 private void writeTypeInfo (ByteVector bv,
141 ClassWriter cw, List info, int max) {
142 if (max > StackMapAttribute.MAX_SIZE) {
143 bv.putInt(info.size());
144 } else {
145 bv.putShort(info.size());
146 }
147 for (int j = 0; j < info.size(); j++) {
148 StackMapType typeInfo = (StackMapType)info.get(j);
149 bv.putByte(typeInfo.getType());
150 switch (typeInfo.getType()) {
151 case StackMapType.ITEM_Object: bv.putShort(cw.newClass(typeInfo.getObject()));
153 break;
154
155 case StackMapType.ITEM_Uninitialized: bv.putShort(typeInfo.getLabel().getOffset());
157 break;
158
159 }
160 }
161 }
162
163 public String toString () {
164 StringBuffer sb = new StringBuffer ("Frame:L");
165 sb.append(System.identityHashCode(label));
166 sb.append(" locals").append(locals);
167 sb.append(" stack").append(stack);
168 return sb.toString();
169 }
170 }
171 |
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