JDK14/Java14源码在线阅读
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bcel /
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generic /
MethodGen.java
/*
* Copyright (c) 2013, 2019, Oracle and/or its affiliates. All rights reserved.
*/
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.sun.org.apache.bcel.internal.generic;
import com.sun.org.apache.bcel.internal.Const;
import com.sun.org.apache.bcel.internal.classfile.AnnotationEntry;
import com.sun.org.apache.bcel.internal.classfile.Annotations;
import com.sun.org.apache.bcel.internal.classfile.Attribute;
import com.sun.org.apache.bcel.internal.classfile.Code;
import com.sun.org.apache.bcel.internal.classfile.CodeException;
import com.sun.org.apache.bcel.internal.classfile.ExceptionTable;
import com.sun.org.apache.bcel.internal.classfile.LineNumber;
import com.sun.org.apache.bcel.internal.classfile.LineNumberTable;
import com.sun.org.apache.bcel.internal.classfile.LocalVariable;
import com.sun.org.apache.bcel.internal.classfile.LocalVariableTable;
import com.sun.org.apache.bcel.internal.classfile.LocalVariableTypeTable;
import com.sun.org.apache.bcel.internal.classfile.Method;
import com.sun.org.apache.bcel.internal.classfile.ParameterAnnotationEntry;
import com.sun.org.apache.bcel.internal.classfile.ParameterAnnotations;
import com.sun.org.apache.bcel.internal.classfile.RuntimeVisibleParameterAnnotations;
import com.sun.org.apache.bcel.internal.classfile.Utility;
import com.sun.org.apache.bcel.internal.util.BCELComparator;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Stack;
/**
* Template class for building up a method. This is done by defining exception
* handlers, adding thrown exceptions, local variables and attributes, whereas
* the `LocalVariableTable' and `LineNumberTable' attributes will be set
* automatically for the code. Use stripAttributes() if you don't like this.
*
* While generating code it may be necessary to insert NOP operations. You can
* use the `removeNOPs' method to get rid off them.
* The resulting method object can be obtained via the `getMethod()' method.
*
* @version $Id$
* @see InstructionList
* @see Method
* @LastModified: Jun 2019
*/
public class MethodGen extends FieldGenOrMethodGen {
private String class_name;
private Type[] arg_types;
private String[] arg_names;
private int max_locals;
private int max_stack;
private InstructionList il;
private boolean strip_attributes;
private LocalVariableTypeTable local_variable_type_table = null;
private final List<LocalVariableGen> variable_vec = new ArrayList<>();
private final List<LineNumberGen> line_number_vec = new ArrayList<>();
private final List<CodeExceptionGen> exception_vec = new ArrayList<>();
private final List<String> throws_vec = new ArrayList<>();
private final List<Attribute> code_attrs_vec = new ArrayList<>();
private List<AnnotationEntryGen>[] param_annotations; // Array of lists containing AnnotationGen objects
private boolean hasParameterAnnotations = false;
private boolean haveUnpackedParameterAnnotations = false;
private static BCELComparator bcelComparator = new BCELComparator() {
@Override
public boolean equals( final Object o1, final Object o2 ) {
final MethodGen THIS = (MethodGen) o1;
final MethodGen THAT = (MethodGen) o2;
return THIS.getName().equals(THAT.getName())
&& THIS.getSignature().equals(THAT.getSignature());
}
@Override
public int hashCode( final Object o ) {
final MethodGen THIS = (MethodGen) o;
return THIS.getSignature().hashCode() ^ THIS.getName().hashCode();
}
};
/**
* Declare method. If the method is non-static the constructor
* automatically declares a local variable `$this' in slot 0. The
* actual code is contained in the `il' parameter, which may further
* manipulated by the user. But he must take care not to remove any
* instruction (handles) that are still referenced from this object.
*
* For example one may not add a local variable and later remove the
* instructions it refers to without causing havoc. It is safe
* however if you remove that local variable, too.
*
* @param access_flags access qualifiers
* @param return_type method type
* @param arg_types argument types
* @param arg_names argument names (if this is null, default names will be provided
* for them)
* @param method_name name of method
* @param class_name class name containing this method (may be null, if you don't care)
* @param il instruction list associated with this method, may be null only for
* abstract or native methods
* @param cp constant pool
*/
public MethodGen(final int access_flags, final Type return_type, final Type[] arg_types, String[] arg_names,
final String method_name, final String class_name, final InstructionList il, final ConstantPoolGen cp) {
super(access_flags);
setType(return_type);
setArgumentTypes(arg_types);
setArgumentNames(arg_names);
setName(method_name);
setClassName(class_name);
setInstructionList(il);
setConstantPool(cp);
final boolean abstract_ = isAbstract() || isNative();
InstructionHandle start = null;
final InstructionHandle end = null;
if (!abstract_) {
start = il.getStart();
// end == null => live to end of method
/* Add local variables, namely the implicit `this' and the arguments
*/
if (!isStatic() && (class_name != null)) { // Instance method -> `this' is local var 0
addLocalVariable("this", ObjectType.getInstance(class_name), start, end);
}
}
if (arg_types != null) {
final int size = arg_types.length;
for (final Type arg_type : arg_types) {
if (Type.VOID == arg_type) {
throw new ClassGenException("'void' is an illegal argument type for a method");
}
}
if (arg_names != null) { // Names for variables provided?
if (size != arg_names.length) {
throw new ClassGenException("Mismatch in argument array lengths: " + size
+ " vs. " + arg_names.length);
}
} else { // Give them dummy names
arg_names = new String[size];
for (int i = 0; i < size; i++) {
arg_names[i] = "arg" + i;
}
setArgumentNames(arg_names);
}
if (!abstract_) {
for (int i = 0; i < size; i++) {
addLocalVariable(arg_names[i], arg_types[i], start, end);
}
}
}
}
/**
* Instantiate from existing method.
*
* @param m method
* @param class_name class name containing this method
* @param cp constant pool
*/
public MethodGen(final Method m, final String class_name, final ConstantPoolGen cp) {
this(m.getAccessFlags(), Type.getReturnType(m.getSignature()), Type.getArgumentTypes(m
.getSignature()), null /* may be overridden anyway */
, m.getName(), class_name,
((m.getAccessFlags() & (Const.ACC_ABSTRACT | Const.ACC_NATIVE)) == 0)
? new InstructionList(m.getCode().getCode())
: null, cp);
final Attribute[] attributes = m.getAttributes();
for (final Attribute attribute : attributes) {
Attribute a = attribute;
if (a instanceof Code) {
final Code c = (Code) a;
setMaxStack(c.getMaxStack());
setMaxLocals(c.getMaxLocals());
final CodeException[] ces = c.getExceptionTable();
if (ces != null) {
for (final CodeException ce : ces) {
final int type = ce.getCatchType();
ObjectType c_type = null;
if (type > 0) {
final String cen = m.getConstantPool().getConstantString(type,
Const.CONSTANT_Class);
c_type = ObjectType.getInstance(cen);
}
final int end_pc = ce.getEndPC();
final int length = m.getCode().getCode().length;
InstructionHandle end;
if (length == end_pc) { // May happen, because end_pc is exclusive
end = il.getEnd();
} else {
end = il.findHandle(end_pc);
end = end.getPrev(); // Make it inclusive
}
addExceptionHandler(il.findHandle(ce.getStartPC()), end, il.findHandle(ce
.getHandlerPC()), c_type);
}
}
final Attribute[] c_attributes = c.getAttributes();
for (final Attribute c_attribute : c_attributes) {
a = c_attribute;
if (a instanceof LineNumberTable) {
final LineNumber[] ln = ((LineNumberTable) a).getLineNumberTable();
for (final LineNumber l : ln) {
final InstructionHandle ih = il.findHandle(l.getStartPC());
if (ih != null) {
addLineNumber(ih, l.getLineNumber());
}
}
} else if (a instanceof LocalVariableTable) {
updateLocalVariableTable((LocalVariableTable) a);
} else if (a instanceof LocalVariableTypeTable) {
this.local_variable_type_table = (LocalVariableTypeTable) a.copy(cp.getConstantPool());
} else {
addCodeAttribute(a);
}
}
} else if (a instanceof ExceptionTable) {
final String[] names = ((ExceptionTable) a).getExceptionNames();
for (final String name2 : names) {
addException(name2);
}
} else if (a instanceof Annotations) {
final Annotations runtimeAnnotations = (Annotations) a;
final AnnotationEntry[] aes = runtimeAnnotations.getAnnotationEntries();
for (final AnnotationEntry element : aes) {
addAnnotationEntry(new AnnotationEntryGen(element, cp, false));
}
} else {
addAttribute(a);
}
}
}
/**
* Adds a local variable to this method.
*
* @param name variable name
* @param type variable type
* @param slot the index of the local variable, if type is long or double, the next available
* index is slot+2
* @param start from where the variable is valid
* @param end until where the variable is valid
* @param orig_index the index of the local variable prior to any modifications
* @return new local variable object
* @see LocalVariable
*/
public LocalVariableGen addLocalVariable( final String name, final Type type, final int slot,
final InstructionHandle start, final InstructionHandle end, final int orig_index ) {
final byte t = type.getType();
if (t != Const.T_ADDRESS) {
final int add = type.getSize();
if (slot + add > max_locals) {
max_locals = slot + add;
}
final LocalVariableGen l = new LocalVariableGen(slot, name, type, start, end, orig_index);
int i;
if ((i = variable_vec.indexOf(l)) >= 0) {
variable_vec.set(i, l);
} else {
variable_vec.add(l);
}
return l;
}
throw new IllegalArgumentException("Can not use " + type
+ " as type for local variable");
}
/**
* Adds a local variable to this method.
*
* @param name variable name
* @param type variable type
* @param slot the index of the local variable, if type is long or double, the next available
* index is slot+2
* @param start from where the variable is valid
* @param end until where the variable is valid
* @return new local variable object
* @see LocalVariable
*/
public LocalVariableGen addLocalVariable( final String name, final Type type, final int slot,
final InstructionHandle start, final InstructionHandle end ) {
return addLocalVariable(name, type, slot, start, end, slot);
}
/**
* Adds a local variable to this method and assigns an index automatically.
*
* @param name variable name
* @param type variable type
* @param start from where the variable is valid, if this is null,
* it is valid from the start
* @param end until where the variable is valid, if this is null,
* it is valid to the end
* @return new local variable object
* @see LocalVariable
*/
public LocalVariableGen addLocalVariable( final String name, final Type type, final InstructionHandle start,
final InstructionHandle end ) {
return addLocalVariable(name, type, max_locals, start, end);
}
/**
* Remove a local variable, its slot will not be reused, if you do not use
* addLocalVariable with an explicit index argument.
*/
public void removeLocalVariable(final LocalVariableGen l) {
variable_vec.remove(l);
}
/**
* Remove all local variables.
*/
public void removeLocalVariables() {
variable_vec.clear();
}
/*
* If the range of the variable has not been set yet, it will be set to be valid from
* the start to the end of the instruction list.
*
* @return array of declared local variables sorted by index
*/
public LocalVariableGen[] getLocalVariables() {
final int size = variable_vec.size();
final LocalVariableGen[] lg = new LocalVariableGen[size];
variable_vec.toArray(lg);
for (int i = 0; i < size; i++) {
if ((lg[i].getStart() == null) && (il != null)) {
lg[i].setStart(il.getStart());
}
if ((lg[i].getEnd() == null) && (il != null)) {
lg[i].setEnd(il.getEnd());
}
}
if (size > 1) {
Arrays.sort(lg, new Comparator<LocalVariableGen>() {
@Override
public int compare(final LocalVariableGen o1, final LocalVariableGen o2) {
return o1.getIndex() - o2.getIndex();
}
});
}
return lg;
}
/**
* @return `LocalVariableTable' attribute of all the local variables of this method.
*/
public LocalVariableTable getLocalVariableTable( final ConstantPoolGen cp ) {
final LocalVariableGen[] lg = getLocalVariables();
final int size = lg.length;
final LocalVariable[] lv = new LocalVariable[size];
for (int i = 0; i < size; i++) {
lv[i] = lg[i].getLocalVariable(cp);
}
return new LocalVariableTable(cp.addUtf8("LocalVariableTable"), 2 + lv.length * 10, lv, cp
.getConstantPool());
}
/**
* @return `LocalVariableTypeTable' attribute of this method.
*/
public LocalVariableTypeTable getLocalVariableTypeTable() {
return local_variable_type_table;
}
/**
* Give an instruction a line number corresponding to the source code line.
*
* @param ih instruction to tag
* @return new line number object
* @see LineNumber
*/
public LineNumberGen addLineNumber( final InstructionHandle ih, final int src_line ) {
final LineNumberGen l = new LineNumberGen(ih, src_line);
line_number_vec.add(l);
return l;
}
/**
* Remove a line number.
*/
public void removeLineNumber( final LineNumberGen l ) {
line_number_vec.remove(l);
}
/**
* Remove all line numbers.
*/
public void removeLineNumbers() {
line_number_vec.clear();
}
/*
* @return array of line numbers
*/
public LineNumberGen[] getLineNumbers() {
final LineNumberGen[] lg = new LineNumberGen[line_number_vec.size()];
line_number_vec.toArray(lg);
return lg;
}
/**
* @return `LineNumberTable' attribute of all the local variables of this method.
*/
public LineNumberTable getLineNumberTable( final ConstantPoolGen cp ) {
final int size = line_number_vec.size();
final LineNumber[] ln = new LineNumber[size];
for (int i = 0; i < size; i++) {
ln[i] = line_number_vec.get(i).getLineNumber();
}
return new LineNumberTable(cp.addUtf8("LineNumberTable"), 2 + ln.length * 4, ln, cp
.getConstantPool());
}
/**
* Add an exception handler, i.e., specify region where a handler is active and an
* instruction where the actual handling is done.
*
* @param start_pc Start of region (inclusive)
* @param end_pc End of region (inclusive)
* @param handler_pc Where handling is done
* @param catch_type class type of handled exception or null if any
* exception is handled
* @return new exception handler object
*/
public CodeExceptionGen addExceptionHandler( final InstructionHandle start_pc,
final InstructionHandle end_pc, final InstructionHandle handler_pc, final ObjectType catch_type ) {
if ((start_pc == null) || (end_pc == null) || (handler_pc == null)) {
throw new ClassGenException("Exception handler target is null instruction");
}
final CodeExceptionGen c = new CodeExceptionGen(start_pc, end_pc, handler_pc, catch_type);
exception_vec.add(c);
return c;
}
/**
* Remove an exception handler.
*/
public void removeExceptionHandler( final CodeExceptionGen c ) {
exception_vec.remove(c);
}
/**
* Remove all line numbers.
*/
public void removeExceptionHandlers() {
exception_vec.clear();
}
/*
* @return array of declared exception handlers
*/
public CodeExceptionGen[] getExceptionHandlers() {
final CodeExceptionGen[] cg = new CodeExceptionGen[exception_vec.size()];
exception_vec.toArray(cg);
return cg;
}
/**
* @return code exceptions for `Code' attribute
*/
private CodeException[] getCodeExceptions() {
final int size = exception_vec.size();
final CodeException[] c_exc = new CodeException[size];
for (int i = 0; i < size; i++) {
final CodeExceptionGen c = exception_vec.get(i);
c_exc[i] = c.getCodeException(super.getConstantPool());
}
return c_exc;
}
/**
* Add an exception possibly thrown by this method.
*
* @param class_name (fully qualified) name of exception
*/
public void addException( final String class_name ) {
throws_vec.add(class_name);
}
/**
* Remove an exception.
*/
public void removeException( final String c ) {
throws_vec.remove(c);
}
/**
* Remove all exceptions.
*/
public void removeExceptions() {
throws_vec.clear();
}
/*
* @return array of thrown exceptions
*/
public String[] getExceptions() {
final String[] e = new String[throws_vec.size()];
throws_vec.toArray(e);
return e;
}
/**
* @return `Exceptions' attribute of all the exceptions thrown by this method.
*/
private ExceptionTable getExceptionTable( final ConstantPoolGen cp ) {
final int size = throws_vec.size();
final int[] ex = new int[size];
for (int i = 0; i < size; i++) {
ex[i] = cp.addClass(throws_vec.get(i));
}
return new ExceptionTable(cp.addUtf8("Exceptions"), 2 + 2 * size, ex, cp.getConstantPool());
}
/**
* Add an attribute to the code. Currently, the JVM knows about the
* LineNumberTable, LocalVariableTable and StackMap attributes,
* where the former two will be generated automatically and the
* latter is used for the MIDP only. Other attributes will be
* ignored by the JVM but do no harm.
*
* @param a attribute to be added
*/
public void addCodeAttribute( final Attribute a ) {
code_attrs_vec.add(a);
}
/**
* Remove the LocalVariableTypeTable
*/
public void removeLocalVariableTypeTable( ) {
local_variable_type_table = null;
}
/**
* Remove a code attribute.
*/
public void removeCodeAttribute( final Attribute a ) {
code_attrs_vec.remove(a);
}
/**
* Remove all code attributes.
*/
public void removeCodeAttributes() {
local_variable_type_table = null;
code_attrs_vec.clear();
}
/**
* @return all attributes of this method.
*/
public Attribute[] getCodeAttributes() {
final Attribute[] attributes = new Attribute[code_attrs_vec.size()];
code_attrs_vec.toArray(attributes);
return attributes;
}
/**
* @since 6.0
*/
public void addAnnotationsAsAttribute(final ConstantPoolGen cp) {
final Attribute[] attrs = AnnotationEntryGen.getAnnotationAttributes(cp, super.getAnnotationEntries());
for (final Attribute attr : attrs) {
addAttribute(attr);
}
}
/**
* @since 6.0
*/
public void addParameterAnnotationsAsAttribute(final ConstantPoolGen cp) {
if (!hasParameterAnnotations) {
return;
}
final Attribute[] attrs = AnnotationEntryGen.getParameterAnnotationAttributes(cp,param_annotations);
if (attrs != null) {
for (final Attribute attr : attrs) {
addAttribute(attr);
}
}
}
/**
* Get method object. Never forget to call setMaxStack() or setMaxStack(max), respectively,
* before calling this method (the same applies for max locals).
*
* @return method object
*/
public Method getMethod() {
final String signature = getSignature();
final ConstantPoolGen _cp = super.getConstantPool();
final int name_index = _cp.addUtf8(super.getName());
final int signature_index = _cp.addUtf8(signature);
/* Also updates positions of instructions, i.e., their indices
*/
byte[] byte_code = null;
if (il != null) {
byte_code = il.getByteCode();
}
LineNumberTable lnt = null;
LocalVariableTable lvt = null;
/* Create LocalVariableTable and LineNumberTable attributes (for debuggers, e.g.)
*/
if ((variable_vec.size() > 0) && !strip_attributes) {
updateLocalVariableTable(getLocalVariableTable(_cp));
addCodeAttribute(lvt = getLocalVariableTable(_cp));
}
if (local_variable_type_table != null) {
// LocalVariable length in LocalVariableTypeTable is not updated automatically. It's a difference with LocalVariableTable.
if (lvt != null) {
adjustLocalVariableTypeTable(lvt);
}
addCodeAttribute(local_variable_type_table);
}
if ((line_number_vec.size() > 0) && !strip_attributes) {
addCodeAttribute(lnt = getLineNumberTable(_cp));
}
final Attribute[] code_attrs = getCodeAttributes();
/* Each attribute causes 6 additional header bytes
*/
int attrs_len = 0;
for (final Attribute code_attr : code_attrs) {
attrs_len += code_attr.getLength() + 6;
}
final CodeException[] c_exc = getCodeExceptions();
final int exc_len = c_exc.length * 8; // Every entry takes 8 bytes
Code code = null;
if ((il != null) && !isAbstract() && !isNative()) {
// Remove any stale code attribute
final Attribute[] attributes = getAttributes();
for (final Attribute a : attributes) {
if (a instanceof Code) {
removeAttribute(a);
}
}
code = new Code(_cp.addUtf8("Code"), 8 + byte_code.length + // prologue byte code
2 + exc_len + // exceptions
2 + attrs_len, // attributes
max_stack, max_locals, byte_code, c_exc, code_attrs, _cp.getConstantPool());
addAttribute(code);
}
addAnnotationsAsAttribute(_cp);
addParameterAnnotationsAsAttribute(_cp);
ExceptionTable et = null;
if (throws_vec.size() > 0) {
addAttribute(et = getExceptionTable(_cp));
// Add `Exceptions' if there are "throws" clauses
}
final Method m = new Method(super.getAccessFlags(), name_index, signature_index, getAttributes(), _cp
.getConstantPool());
// Undo effects of adding attributes
if (lvt != null) {
removeCodeAttribute(lvt);
}
if (local_variable_type_table != null) {
removeCodeAttribute(local_variable_type_table);
}
if (lnt != null) {
removeCodeAttribute(lnt);
}
if (code != null) {
removeAttribute(code);
}
if (et != null) {
removeAttribute(et);
}
return m;
}
private void updateLocalVariableTable(final LocalVariableTable a) {
final LocalVariable[] lv = a.getLocalVariableTable();
removeLocalVariables();
for (final LocalVariable l : lv) {
InstructionHandle start = il.findHandle(l.getStartPC());
final InstructionHandle end = il.findHandle(l.getStartPC() + l.getLength());
// Repair malformed handles
if (null == start) {
start = il.getStart();
}
// end == null => live to end of method
// Since we are recreating the LocalVaraible, we must
// propagate the orig_index to new copy.
addLocalVariable(l.getName(), Type.getType(l.getSignature()), l
.getIndex(), start, end, l.getOrigIndex());
}
}
private void adjustLocalVariableTypeTable(final LocalVariableTable lvt) {
final LocalVariable[] lv = lvt.getLocalVariableTable();
final LocalVariable[] lvg = local_variable_type_table.getLocalVariableTypeTable();
for (final LocalVariable element : lvg) {
for (final LocalVariable l : lv) {
if (element.getName().equals(l.getName()) && element.getIndex() == l.getOrigIndex()) {
element.setLength(l.getLength());
element.setStartPC(l.getStartPC());
element.setIndex(l.getIndex());
break;
}
}
}
}
/**
* Remove all NOPs from the instruction list (if possible) and update every
* object referring to them, i.e., branch instructions, local variables and
* exception handlers.
*/
public void removeNOPs() {
if (il != null) {
InstructionHandle next;
/* Check branch instructions.
*/
for (InstructionHandle ih = il.getStart(); ih != null; ih = next) {
next = ih.getNext();
if ((next != null) && (ih.getInstruction() instanceof NOP)) {
try {
il.delete(ih);
} catch (final TargetLostException e) {
for (final InstructionHandle target : e.getTargets()) {
for (final InstructionTargeter targeter : target.getTargeters()) {
targeter.updateTarget(target, next);
}
}
}
}
}
}
}
/**
* Set maximum number of local variables.
*/
public void setMaxLocals( final int m ) {
max_locals = m;
}
public int getMaxLocals() {
return max_locals;
}
/**
* Set maximum stack size for this method.
*/
public void setMaxStack( final int m ) { // TODO could be package-protected?
max_stack = m;
}
public int getMaxStack() {
return max_stack;
}
/** @return class that contains this method
*/
public String getClassName() {
return class_name;
}
public void setClassName( final String class_name ) { // TODO could be package-protected?
this.class_name = class_name;
}
public void setReturnType( final Type return_type ) {
setType(return_type);
}
public Type getReturnType() {
return getType();
}
public void setArgumentTypes( final Type[] arg_types ) {
this.arg_types = arg_types;
}
public Type[] getArgumentTypes() {
return arg_types.clone();
}
public void setArgumentType( final int i, final Type type ) {
arg_types[i] = type;
}
public Type getArgumentType( final int i ) {
return arg_types[i];
}
public void setArgumentNames( final String[] arg_names ) {
this.arg_names = arg_names;
}
public String[] getArgumentNames() {
return arg_names.clone();
}
public void setArgumentName( final int i, final String name ) {
arg_names[i] = name;
}
public String getArgumentName( final int i ) {
return arg_names[i];
}
public InstructionList getInstructionList() {
return il;
}
public void setInstructionList( final InstructionList il ) { // TODO could be package-protected?
this.il = il;
}
@Override
public String getSignature() {
return Type.getMethodSignature(super.getType(), arg_types);
}
/**
* Computes max. stack size by performing control flow analysis.
*/
public void setMaxStack() { // TODO could be package-protected? (some tests would need repackaging)
if (il != null) {
max_stack = getMaxStack(super.getConstantPool(), il, getExceptionHandlers());
} else {
max_stack = 0;
}
}
/**
* Compute maximum number of local variables.
*/
public void setMaxLocals() { // TODO could be package-protected? (some tests would need repackaging)
if (il != null) {
int max = isStatic() ? 0 : 1;
if (arg_types != null) {
for (final Type arg_type : arg_types) {
max += arg_type.getSize();
}
}
for (InstructionHandle ih = il.getStart(); ih != null; ih = ih.getNext()) {
final Instruction ins = ih.getInstruction();
if ((ins instanceof LocalVariableInstruction) || (ins instanceof RET)
|| (ins instanceof IINC)) {
final int index = ((IndexedInstruction) ins).getIndex()
+ ((TypedInstruction) ins).getType(super.getConstantPool()).getSize();
if (index > max) {
max = index;
}
}
}
max_locals = max;
} else {
max_locals = 0;
}
}
/** Do not/Do produce attributes code attributesLineNumberTable and
* LocalVariableTable, like javac -O
*/
public void stripAttributes( final boolean flag ) {
strip_attributes = flag;
}
static final class BranchTarget {
final InstructionHandle target;
final int stackDepth;
BranchTarget(final InstructionHandle target, final int stackDepth) {
this.target = target;
this.stackDepth = stackDepth;
}
}
static final class BranchStack {
private final Stack<BranchTarget> branchTargets = new Stack<>();
private final Map<InstructionHandle, BranchTarget> visitedTargets = new HashMap<>();
public void push( final InstructionHandle target, final int stackDepth ) {
if (visited(target)) {
return;
}
branchTargets.push(visit(target, stackDepth));
}
public BranchTarget pop() {
if (!branchTargets.empty()) {
final BranchTarget bt = branchTargets.pop();
return bt;
}
return null;
}
private BranchTarget visit( final InstructionHandle target, final int stackDepth ) {
final BranchTarget bt = new BranchTarget(target, stackDepth);
visitedTargets.put(target, bt);
return bt;
}
private boolean visited( final InstructionHandle target ) {
return visitedTargets.get(target) != null;
}
}
/**
* Computes stack usage of an instruction list by performing control flow analysis.
*
* @return maximum stack depth used by method
*/
public static int getMaxStack( final ConstantPoolGen cp, final InstructionList il, final CodeExceptionGen[] et ) {
final BranchStack branchTargets = new BranchStack();
/* Initially, populate the branch stack with the exception
* handlers, because these aren't (necessarily) branched to
* explicitly. in each case, the stack will have depth 1,
* containing the exception object.
*/
for (final CodeExceptionGen element : et) {
final InstructionHandle handler_pc = element.getHandlerPC();
if (handler_pc != null) {
branchTargets.push(handler_pc, 1);
}
}
int stackDepth = 0;
int maxStackDepth = 0;
InstructionHandle ih = il.getStart();
while (ih != null) {
final Instruction instruction = ih.getInstruction();
final short opcode = instruction.getOpcode();
final int delta = instruction.produceStack(cp) - instruction.consumeStack(cp);
stackDepth += delta;
if (stackDepth > maxStackDepth) {
maxStackDepth = stackDepth;
}
// choose the next instruction based on whether current is a branch.
if (instruction instanceof BranchInstruction) {
final BranchInstruction branch = (BranchInstruction) instruction;
if (instruction instanceof Select) {
// explore all of the select's targets. the default target is handled below.
final Select select = (Select) branch;
final InstructionHandle[] targets = select.getTargets();
for (final InstructionHandle target : targets) {
branchTargets.push(target, stackDepth);
}
// nothing to fall through to.
ih = null;
} else if (!(branch instanceof IfInstruction)) {
// if an instruction that comes back to following PC,
// push next instruction, with stack depth reduced by 1.
if (opcode == Const.JSR || opcode == Const.JSR_W) {
branchTargets.push(ih.getNext(), stackDepth - 1);
}
ih = null;
}
// for all branches, the target of the branch is pushed on the branch stack.
// conditional branches have a fall through case, selects don't, and
// jsr/jsr_w return to the next instruction.
branchTargets.push(branch.getTarget(), stackDepth);
} else {
// check for instructions that terminate the method.
if (opcode == Const.ATHROW || opcode == Const.RET
|| (opcode >= Const.IRETURN && opcode <= Const.RETURN)) {
ih = null;
}
}
// normal case, go to the next instruction.
if (ih != null) {
ih = ih.getNext();
}
// if we have no more instructions, see if there are any deferred branches to explore.
if (ih == null) {
final BranchTarget bt = branchTargets.pop();
if (bt != null) {
ih = bt.target;
stackDepth = bt.stackDepth;
}
}
}
return maxStackDepth;
}
private List<MethodObserver> observers;
/** Add observer for this object.
*/
public void addObserver( final MethodObserver o ) {
if (observers == null) {
observers = new ArrayList<>();
}
observers.add(o);
}
/** Remove observer for this object.
*/
public void removeObserver( final MethodObserver o ) {
if (observers != null) {
observers.remove(o);
}
}
/** Call notify() method on all observers. This method is not called
* automatically whenever the state has changed, but has to be
* called by the user after he has finished editing the object.
*/
public void update() {
if (observers != null) {
for (final MethodObserver observer : observers) {
observer.notify(this);
}
}
}
/**
* Return string representation close to declaration format,
* `public static void main(String[]) throws IOException', e.g.
*
* @return String representation of the method.
*/
@Override
public final String toString() {
final String access = Utility.accessToString(super.getAccessFlags());
String signature = Type.getMethodSignature(super.getType(), arg_types);
signature = Utility.methodSignatureToString(signature, super.getName(), access, true,
getLocalVariableTable(super.getConstantPool()));
final StringBuilder buf = new StringBuilder(signature);
for (final Attribute a : getAttributes()) {
if (!((a instanceof Code) || (a instanceof ExceptionTable))) {
buf.append(" [").append(a).append("]");
}
}
if (throws_vec.size() > 0) {
for (final String throwsDescriptor : throws_vec) {
buf.append("\n\t\tthrows ").append(throwsDescriptor);
}
}
return buf.toString();
}
/** @return deep copy of this method
*/
public MethodGen copy( final String class_name, final ConstantPoolGen cp ) {
final Method m = ((MethodGen) clone()).getMethod();
final MethodGen mg = new MethodGen(m, class_name, super.getConstantPool());
if (super.getConstantPool() != cp) {
mg.setConstantPool(cp);
mg.getInstructionList().replaceConstantPool(super.getConstantPool(), cp);
}
return mg;
}
//J5TODO: Should param_annotations be an array of arrays? Rather than an array of lists, this
// is more likely to suggest to the caller it is readonly (which a List does not).
/**
* Return a list of AnnotationGen objects representing parameter annotations
* @since 6.0
*/
public List<AnnotationEntryGen> getAnnotationsOnParameter(final int i) {
ensureExistingParameterAnnotationsUnpacked();
if (!hasParameterAnnotations || i > arg_types.length) {
return null;
}
return param_annotations[i];
}
/**
* Goes through the attributes on the method and identifies any that are
* RuntimeParameterAnnotations, extracting their contents and storing them
* as parameter annotations. There are two kinds of parameter annotation -
* visible and invisible. Once they have been unpacked, these attributes are
* deleted. (The annotations will be rebuilt as attributes when someone
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