001: /***
002: * ASM: a very small and fast Java bytecode manipulation framework
003: * Copyright (c) 2000-2005 INRIA, France Telecom
004: * All rights reserved.
005: *
006: * Redistribution and use in source and binary forms, with or without
007: * modification, are permitted provided that the following conditions
008: * are met:
009: * 1. Redistributions of source code must retain the above copyright
010: * notice, this list of conditions and the following disclaimer.
011: * 2. Redistributions in binary form must reproduce the above copyright
012: * notice, this list of conditions and the following disclaimer in the
013: * documentation and/or other materials provided with the distribution.
014: * 3. Neither the name of the copyright holders nor the names of its
015: * contributors may be used to endorse or promote products derived from
016: * this software without specific prior written permission.
017: *
018: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
019: * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
020: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
021: * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
022: * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
023: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
024: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
025: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
026: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
027: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
028: * THE POSSIBILITY OF SUCH DAMAGE.
029: */package org.ejb3unit.asm.tree.analysis;
030:
031: import java.util.List;
032:
033: import org.ejb3unit.asm.Type;
034: import org.ejb3unit.asm.tree.AbstractInsnNode;
035:
036: /**
037: * A semantic bytecode interpreter. More precisely, this interpreter only
038: * manages the computation of values from other values: it does not manage the
039: * transfer of values to or from the stack, and to or from the local variables.
040: * This separation allows a generic bytecode {@link Analyzer} to work with
041: * various semantic interpreters, without needing to duplicate the code to
042: * simulate the transfer of values.
043: *
044: * @author Eric Bruneton
045: */
046: public interface Interpreter {
047:
048: /**
049: * Creates a new value that represents the given type.
050: *
051: * Called for method parameters (including <code>this</code>), exception
052: * handler variable and with <code>null</code> type for variables reserved
053: * by long and double types.
054: *
055: * @param type
056: * a primitive or reference type, or <tt>null</tt> to represent
057: * an uninitialized value.
058: * @return a value that represents the given type. The size of the returned
059: * value must be equal to the size of the given type.
060: */
061: Value newValue(Type type);
062:
063: /**
064: * Interprets a bytecode instruction without arguments. This method is
065: * called for the following opcodes:
066: *
067: * ACONST_NULL, ICONST_M1, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4,
068: * ICONST_5, LCONST_0, LCONST_1, FCONST_0, FCONST_1, FCONST_2, DCONST_0,
069: * DCONST_1, BIPUSH, SIPUSH, LDC, JSR, GETSTATIC, NEW
070: *
071: * @param insn
072: * the bytecode instruction to be interpreted.
073: * @return the result of the interpretation of the given instruction.
074: * @throws AnalyzerException
075: * if an error occured during the interpretation.
076: */
077: Value newOperation(AbstractInsnNode insn) throws AnalyzerException;
078:
079: /**
080: * Interprets a bytecode instruction that moves a value on the stack or to
081: * or from local variables. This method is called for the following opcodes:
082: *
083: * ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE, LSTORE, FSTORE, DSTORE,
084: * ASTORE, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP
085: *
086: * @param insn
087: * the bytecode instruction to be interpreted.
088: * @param value
089: * the value that must be moved by the instruction.
090: * @return the result of the interpretation of the given instruction. The
091: * returned value must be <tt>equal</tt> to the given value.
092: * @throws AnalyzerException
093: * if an error occured during the interpretation.
094: */
095: Value copyOperation(AbstractInsnNode insn, Value value)
096: throws AnalyzerException;
097:
098: /**
099: * Interprets a bytecode instruction with a single argument. This method is
100: * called for the following opcodes:
101: *
102: * INEG, LNEG, FNEG, DNEG, IINC, I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L,
103: * F2D, D2I, D2L, D2F, I2B, I2C, I2S, IFEQ, IFNE, IFLT, IFGE, IFGT, IFLE,
104: * TABLESWITCH, LOOKUPSWITCH, IRETURN, LRETURN, FRETURN, DRETURN, ARETURN,
105: * PUTSTATIC, GETFIELD, NEWARRAY, ANEWARRAY, ARRAYLENGTH, ATHROW, CHECKCAST,
106: * INSTANCEOF, MONITORENTER, MONITOREXIT, IFNULL, IFNONNULL
107: *
108: * @param insn
109: * the bytecode instruction to be interpreted.
110: * @param value
111: * the argument of the instruction to be interpreted.
112: * @return the result of the interpretation of the given instruction.
113: * @throws AnalyzerException
114: * if an error occured during the interpretation.
115: */
116: Value unaryOperation(AbstractInsnNode insn, Value value)
117: throws AnalyzerException;
118:
119: /**
120: * Interprets a bytecode instruction with two arguments. This method is
121: * called for the following opcodes:
122: *
123: * IALOAD, LALOAD, FALOAD, DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IADD,
124: * LADD, FADD, DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV,
125: * LDIV, FDIV, DDIV, IREM, LREM, FREM, DREM, ISHL, LSHL, ISHR, LSHR, IUSHR,
126: * LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR, LCMP, FCMPL, FCMPG, DCMPL,
127: * DCMPG, IF_ICMPEQ, IF_ICMPNE, IF_ICMPLT, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE,
128: * IF_ACMPEQ, IF_ACMPNE, PUTFIELD
129: *
130: * @param insn
131: * the bytecode instruction to be interpreted.
132: * @param value1
133: * the first argument of the instruction to be interpreted.
134: * @param value2
135: * the second argument of the instruction to be interpreted.
136: * @return the result of the interpretation of the given instruction.
137: * @throws AnalyzerException
138: * if an error occured during the interpretation.
139: */
140: Value binaryOperation(AbstractInsnNode insn, Value value1,
141: Value value2) throws AnalyzerException;
142:
143: /**
144: * Interprets a bytecode instruction with three arguments. This method is
145: * called for the following opcodes:
146: *
147: * IASTORE, LASTORE, FASTORE, DASTORE, AASTORE, BASTORE, CASTORE, SASTORE
148: *
149: * @param insn
150: * the bytecode instruction to be interpreted.
151: * @param value1
152: * the first argument of the instruction to be interpreted.
153: * @param value2
154: * the second argument of the instruction to be interpreted.
155: * @param value3
156: * the third argument of the instruction to be interpreted.
157: * @return the result of the interpretation of the given instruction.
158: * @throws AnalyzerException
159: * if an error occured during the interpretation.
160: */
161: Value ternaryOperation(AbstractInsnNode insn, Value value1,
162: Value value2, Value value3) throws AnalyzerException;
163:
164: /**
165: * Interprets a bytecode instruction with a variable number of arguments.
166: * This method is called for the following opcodes:
167: *
168: * INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC, INVOKEINTERFACE,
169: * MULTIANEWARRAY
170: *
171: * @param insn
172: * the bytecode instruction to be interpreted.
173: * @param values
174: * the arguments of the instruction to be interpreted.
175: * @return the result of the interpretation of the given instruction.
176: * @throws AnalyzerException
177: * if an error occured during the interpretation.
178: */
179: Value naryOperation(AbstractInsnNode insn, List values)
180: throws AnalyzerException;
181:
182: /**
183: * Merges two values. The merge operation must return a value that
184: * represents both values (for instance, if the two values are two types,
185: * the merged value must be a common super type of the two types. If the two
186: * values are integer intervals, the merged value must be an interval that
187: * contains the previous ones. Likewise for other types of values).
188: *
189: * @param v
190: * a value.
191: * @param w
192: * another value.
193: * @return the merged value. If the merged value is equal to <tt>v</tt>,
194: * this method <i>must</i> return <tt>v</tt>.
195: */
196: Value merge(Value v, Value w);
197: }
|