1 cananian 1.1.2.2 // LocalVariableTable.java, created Mon Jan 18 22:44:38 1999 by cananian
2 cananian 1.1.2.1 // Copyright (C) 1998 C. Scott Ananian <cananian@alumni.princeton.edu>
3 cananian 1.1.2.1 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 cananian 1.1.2.1 package harpoon.IR.RawClass;
5 cananian 1.1.2.1
6 cananian 1.1.2.1 /**
7 cananian 1.1.2.1 * Each object indicates a range of <code>code</code> array offsets
8 cananian 1.1.2.1 * within which a local variable has a value.
9 cananian 1.1.2.1 *
10 cananian 1.1.2.1 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
11 cananian 1.2 * @version $Id: LocalVariableTable.java,v 1.2 2002/02/25 21:05:27 cananian Exp $
12 cananian 1.1.2.1 * @see AttributeLocalVariableTable
13 cananian 1.1.2.1 */
14 cananian 1.1.2.1 public class LocalVariableTable {
15 cananian 1.1.2.1 /** ClassFile in which this attribute information is found. */
16 cananian 1.1.2.1 protected ClassFile parent;
17 cananian 1.1.2.1
18 cananian 1.1.2.1 /** The given local variable must have a value at indices into the
19 cananian 1.1.2.1 <code>code</code> array in the closed interval
20 cananian 1.1.2.1 <code>[start_pc, start_pc + length]</code>.
21 cananian 1.1.2.1 <p> The value of <code>start_pc</code> must be a valid index
22 cananian 1.1.2.1 into the <code>code</code> array of this <code>Code</code>
23 cananian 1.1.2.1 attribute of the opcode of an instruction. */
24 cananian 1.1.2.1 public int start_pc;
25 cananian 1.1.2.1 /** The given local variable must have a value at indices into the
26 cananian 1.1.2.1 <code>code</code> array in the closed interval
27 cananian 1.1.2.1 <code>[start_pc, start_pc + length]</code>.
28 cananian 1.1.2.1 <p> The value of <code>start_pc+length</code> must be either a
29 cananian 1.1.2.1 valid index into the <code>code</code> array of this
30 cananian 1.1.2.1 <code>Code</code> attribute of the opcode of an instruction,
31 cananian 1.1.2.1 or the first index beyond the end of that <code>code</code>
32 cananian 1.1.2.1 array. */
33 cananian 1.1.2.1 public int length;
34 cananian 1.1.2.1 /** The value of the <code>name_index</code> item must be a valid
35 cananian 1.1.2.1 index into the <code>constant_pool</code> table. The
36 cananian 1.1.2.1 <code>constant_pool</code> entry at that index must contain a
37 cananian 1.1.2.1 <code>CONSTANT_Utf8_info</codE> structure representing a valid
38 cananian 1.1.2.1 Java local variable name stored as a simple name. */
39 cananian 1.1.2.1 public int name_index;
40 cananian 1.1.2.1 /** The value of the <code>descriptor_index</code> item must be a
41 cananian 1.1.2.1 valid index into the <code>constant_pool</code> table. The
42 cananian 1.1.2.1 <code>constant_pool</code> entry at that index must contain a
43 cananian 1.1.2.1 <code>CONSTANT_Utf8_info</code> structure representing a valid
44 cananian 1.1.2.1 descriptor for a Java local variable. Java local variable
45 cananian 1.1.2.1 descriptors have the same form as field descriptors. */
46 cananian 1.1.2.1 public int descriptor_index;
47 cananian 1.1.2.1 /** The given local variable must be at <code>index</code> in its
48 cananian 1.1.2.1 method's local variables. If the local variable at
49 cananian 1.1.2.1 <code>index</code> is a two-word type (<code>double</code> or
50 cananian 1.1.2.1 <code>long</code>), it occupies both <code>index</code> and
51 cananian 1.1.2.1 <code>index+1</code>. */
52 cananian 1.1.2.1 public int index;
53 cananian 1.1.2.1
54 cananian 1.1.2.1 /** Constructor. */
55 cananian 1.1.2.1 LocalVariableTable(ClassFile parent, ClassDataInputStream in)
56 cananian 1.1.2.1 throws java.io.IOException {
57 cananian 1.1.2.1 this.parent = parent;
58 cananian 1.1.2.1
59 cananian 1.1.2.1 this.start_pc = in.read_u2();
60 cananian 1.1.2.1 this.length = in.read_u2();
61 cananian 1.1.2.1
62 cananian 1.1.2.1 this.name_index = in.read_u2();
63 cananian 1.1.2.1 this.descriptor_index = in.read_u2();
64 cananian 1.1.2.1
65 cananian 1.1.2.1 this.index = in.read_u2();
66 cananian 1.1.2.1 }
67 cananian 1.1.2.1 /** Constructor. */
68 cananian 1.1.2.1 public LocalVariableTable(ClassFile parent,
69 cananian 1.1.2.1 int start_pc, int length,
70 cananian 1.1.2.1 int name_index, int descriptor_index,
71 cananian 1.1.2.1 int index) {
72 cananian 1.1.2.1 this.parent = parent;
73 cananian 1.1.2.1
74 cananian 1.1.2.1 this.start_pc = start_pc;
75 cananian 1.1.2.1 this.length = length;
76 cananian 1.1.2.1 this.name_index = name_index;
77 cananian 1.1.2.1 this.descriptor_index = descriptor_index;
78 cananian 1.1.2.1 this.index = index;
79 cananian 1.1.2.1 }
80 cananian 1.1.2.1 /** Writes to bytecode stream. */
81 cananian 1.1.2.1 public void write(ClassDataOutputStream out) throws java.io.IOException {
82 cananian 1.1.2.1 out.write_u2(start_pc);
83 cananian 1.1.2.1 out.write_u2(length);
84 cananian 1.1.2.1
85 cananian 1.1.2.1 out.write_u2(name_index);
86 cananian 1.1.2.1 out.write_u2(descriptor_index);
87 cananian 1.1.2.1
88 cananian 1.1.2.1 out.write_u2(index);
89 cananian 1.1.2.1 }
90 cananian 1.1.2.1 // convenience functions.
91 cananian 1.1.2.1 public ConstantUtf8 name_index()
92 cananian 1.1.2.1 { return (ConstantUtf8) parent.constant_pool[name_index]; }
93 cananian 1.1.2.1 public ConstantUtf8 descriptor_index()
94 cananian 1.1.2.1 { return (ConstantUtf8) parent.constant_pool[descriptor_index]; }
95 cananian 1.1.2.1
96 cananian 1.1.2.1 public String name() { return name_index().val; }
97 cananian 1.1.2.1 public String descriptor() { return descriptor_index().val; }
98 cananian 1.1.2.1
99 cananian 1.1.2.1 public int end_pc() { return start_pc + length; }
100 cananian 1.1.2.1
101 cananian 1.1.2.1 /** Pretty-print the contents of this attribute.
102 cananian 1.1.2.1 * @param indent the indentation level to use.
103 cananian 1.1.2.1 */
104 cananian 1.1.2.1 public void print(java.io.PrintWriter pw, int indent) {
105 cananian 1.1.2.1 int in=indent;
106 cananian 1.1.2.1 indent(pw, in, "Valid in pc=["+start_pc+","+(start_pc+length)+"]");
107 cananian 1.1.2.1 indent(pw, in, "Variable index: "+index);
108 cananian 1.1.2.1 indent(pw, in, "Variable name: "+name()+" {"+name_index+"}");
109 cananian 1.1.2.1 indent(pw, in, "Descriptor: "+descriptor()+" {"+descriptor_index+"}");
110 cananian 1.1.2.1 }
111 cananian 1.1.2.1 private static void indent(java.io.PrintWriter pw, int indent, String s) {
112 cananian 1.1.2.1 ClassFile.indent(pw,indent,s);
113 cananian 1.1.2.1 }
114 cananian 1.2 }