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1 package org.python.compiler;
3
4 import java.util.*;
5 import java.io.*;
6
7 class Bytes
8 {
9 public byte[] data;
10
11 Bytes(ByteArrayOutputStream data) {
12 this.data = data.toByteArray();
13 }
14
15 public boolean equals(Object  o) {
16 if (o instanceof Bytes) {
17 byte[] odata = ((Bytes)o).data;
18 int n = data.length;
19 if (odata.length != n)
20 return false;
21 for (int i=0; i<n; i++) {
22 if (data[i] != odata[i])
23 return false;
24 }
25 return true;
26 }
27 return false;
28 }
29
30 public int hashCode() {
31 int h = 0xa538;
32 int n = data.length;
33 for (int i=0; i<n; i++)
34 h = h ^ data[i];
35 return h;
36 }
37 }
38
39 public class ConstantPool
40 {
41 Hashtable constants;
42 int index;
43 DataOutputStream tdata;
44 ByteArrayOutputStream pool, tarray;
45 int[] sizes;
46
47 public ConstantPool() {
48 constants = new Hashtable();
49 index = 0;
50 pool = new ByteArrayOutputStream();
51 tarray = new ByteArrayOutputStream();
52 tdata = new DataOutputStream(tarray);
53 sizes = new int[256];
54 }
55
56 public void write(DataOutputStream stream) throws IOException {
57 stream.writeShort(index+1);
58 stream.write(pool.toByteArray());
59 }
60
61 public int addConstant(int slots) throws IOException {
62 Bytes data = new Bytes(tarray);
65 tarray.reset();
66 Integer i = (Integer )constants.get(data);
67 if (i == null) {
68 pool.write(data.data);
69 i = new Integer (index);
70 constants.put(data, i);
71 if (index+1 >= sizes.length) {
72 int[] new_sizes = new int[sizes.length*2];
73 System.arraycopy(sizes, 0, new_sizes, 0, sizes.length);
74 sizes = new_sizes;
75 }
76 sizes[index+1] = slots;
77 index += slots;
78 }
79 return i.intValue()+1;
84 }
85
86 public int UTF8(String s) throws IOException {
87 tdata.writeByte(1);
88 tdata.writeUTF(s);
89 return addConstant(1);
90 }
91
92 public int Class(String s) throws IOException {
93 int c = UTF8(s);
94 tdata.writeByte(7);
95 tdata.writeShort(c);
96 return addConstant(1);
97 }
98
99 public int Fieldref(String c, String name, String type)
100 throws IOException
101 {
102 int ic = Class(c);
103 int nt = NameAndType(name, type);
104 tdata.writeByte(9);
105 tdata.writeShort(ic);
106 tdata.writeShort(nt);
107 int size = 1;
108 if (type.equals("D") || type.equals("J"))
109 size = 2;
110 int index = addConstant(1);
111 sizes[index] = size;
112 return index;
114 }
115
116 public static int sigSize(String sig, boolean includeReturn) {
117 int stack = 0;
118 int i = 0;
119 char[] c = sig.toCharArray();
120 int n = c.length;
121 boolean ret=false;
122 boolean array=false;
123
124 while (++i<n) {
125 switch (c[i]) {
126 case ')':
127 if (!includeReturn)
128 return stack;
129 ret=true;
130 continue;
131 case '[':
132 array=true;
133 continue;
134 case 'V':
135 continue;
136 case 'D':
137 case 'J':
138 if (array) {
139 if (ret) stack += 1;
140 else stack -=1;
141 array = false;
142 } else {
143 if (ret) stack += 2;
144 else stack -=2;
145 }
146 break;
147 case 'L':
148 while (c[++i] != ';') {;}
149 default:
150 if (ret) stack++;
151 else stack--;
152 array = false;
153 }
154 }
155 return stack;
156 }
157
158 public int Methodref(String c, String name, String type)
159 throws IOException
160 {
161 int ic = Class(c);
162 int nt = NameAndType(name, type);
163
164 tdata.writeByte(10);
165 tdata.writeShort(ic);
166 tdata.writeShort(nt);
167 int index = addConstant(1);
168 sizes[index] = sigSize(type, true);
169 return index;
171 }
172
173 public int InterfaceMethodref(String c, String name, String type)
174 throws IOException
175 {
176 int ic = Class(c);
177 int nt = NameAndType(name, type);
178
179 tdata.writeByte(11);
180 tdata.writeShort(ic);
181 tdata.writeShort(nt);
182 int index = addConstant(1);
183 sizes[index] = sigSize(type, true);
184 return index;
185 }
186
187 public int String(String s) throws IOException {
188 int i = UTF8(s);
189 tdata.writeByte(8);
190 tdata.writeShort(i);
191 return addConstant(1);
192 }
193
194 public int Integer(int i) throws IOException {
195 tdata.writeByte(3);
196 tdata.writeInt(i);
197 return addConstant(1);
198 }
199
200 public int Float(float f) throws IOException {
201 tdata.writeByte(4);
202 tdata.writeFloat(f);
203 return addConstant(1);
204 }
205
206 public int Long(long l) throws IOException {
207 tdata.writeByte(5);
208 tdata.writeLong(l);
209 return addConstant(2);
210 }
211
212 public int Double(double d) throws IOException {
213 tdata.writeByte(6);
214 tdata.writeDouble(d);
215 return addConstant(2);
216 }
217
218 public int NameAndType(String name, String type) throws IOException {
219 int n = UTF8(name);
220 int t = UTF8(type);
221
222 tdata.writeByte(12);
223 tdata.writeShort(n);
224 tdata.writeShort(t);
225 return addConstant(1);
226 }
227
228 public static void main(String [] args) throws Exception {
229 ConstantPool cp = new ConstantPool();
230
231 System.out.println("c: "+cp.Class("org/python/core/PyString"));
232 System.out.println("c: "+cp.Class("org/python/core/PyString"));
233
234 for (int i=0; i<args.length; i++)
235 System.out.println(args[i]+": "+sigSize(args[i], true));
236 }
237 }
238 |
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