/*
* Copyright 2000-2014 JetBrains s.r.o.
*
* Licensed 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 org.jetbrains.java.decompiler.main;
import org.jetbrains.java.decompiler.code.CodeConstants;
import org.jetbrains.java.decompiler.main.ClassesProcessor.ClassNode;
import org.jetbrains.java.decompiler.main.extern.IFernflowerPreferences;
import org.jetbrains.java.decompiler.main.rels.ClassWrapper;
import org.jetbrains.java.decompiler.main.rels.MethodWrapper;
import org.jetbrains.java.decompiler.modules.decompiler.exps.*;
import org.jetbrains.java.decompiler.modules.decompiler.stats.RootStatement;
import org.jetbrains.java.decompiler.modules.decompiler.stats.Statement;
import org.jetbrains.java.decompiler.modules.decompiler.vars.VarVersionPaar;
import org.jetbrains.java.decompiler.struct.StructClass;
import org.jetbrains.java.decompiler.struct.StructField;
import org.jetbrains.java.decompiler.util.InterpreterUtil;
import java.util.ArrayList;
import java.util.List;
public class InitializerProcessor {
public static void extractInitializers(ClassWrapper wrapper) {
MethodWrapper meth = wrapper.getMethodWrapper("<clinit>", "()V");
if (meth != null && meth.root != null) { // successfully decompiled static constructor
extractStaticInitializers(wrapper, meth);
}
extractDynamicInitializers(wrapper);
// required e.g. if anonymous class is being decompiled as a standard one.
// This can happen if InnerClasses attributes are erased
liftConstructor(wrapper);
if (DecompilerContext.getOption(IFernflowerPreferences.HIDE_EMPTY_SUPER)) {
hideEmptySuper(wrapper);
}
}
private static void liftConstructor(ClassWrapper wrapper) {
for (MethodWrapper meth : wrapper.getMethods()) {
if ("<init>".equals(meth.methodStruct.getName()) && meth.root != null) {
Statement firstdata = findFirstData(meth.root);
if (firstdata == null) {
return;
}
int index = 0;
List<Exprent> lstExprents = firstdata.getExprents();
for (Exprent exprent : lstExprents) {
int action = 0;
if (exprent.type == Exprent.EXPRENT_ASSIGNMENT) {
AssignmentExprent asexpr = (AssignmentExprent)exprent;
if (asexpr.getLeft().type == Exprent.EXPRENT_FIELD && asexpr.getRight().type == Exprent.EXPRENT_VAR) {
FieldExprent fexpr = (FieldExprent)asexpr.getLeft();
if (fexpr.getClassname().equals(wrapper.getClassStruct().qualifiedName)) {
StructField structField = wrapper.getClassStruct().getField(fexpr.getName(), fexpr.getDescriptor().descriptorString);
if (structField != null && structField.hasModifier(CodeConstants.ACC_FINAL)) {
action = 1;
}
}
}
}
else if (index > 0 && exprent.type == Exprent.EXPRENT_INVOCATION &&
isInvocationInitConstructor((InvocationExprent)exprent, meth, wrapper, true)) {
// this() or super()
lstExprents.add(0, lstExprents.remove(index));
action = 2;
}
if (action != 1) {
break;
}
index++;
}
}
}
}
private static void hideEmptySuper(ClassWrapper wrapper) {
for (MethodWrapper meth : wrapper.getMethods()) {
if ("<init>".equals(meth.methodStruct.getName()) && meth.root != null) {
Statement firstdata = findFirstData(meth.root);
if (firstdata == null || firstdata.getExprents().isEmpty()) {
return;
}
Exprent exprent = firstdata.getExprents().get(0);
if (exprent.type == Exprent.EXPRENT_INVOCATION) {
InvocationExprent invexpr = (InvocationExprent)exprent;
if (isInvocationInitConstructor(invexpr, meth, wrapper, false) && invexpr.getLstParameters().isEmpty()) {
firstdata.getExprents().remove(0);
}
}
}
}
}
private static void extractStaticInitializers(ClassWrapper wrapper, MethodWrapper meth) {
RootStatement root = meth.root;
StructClass cl = wrapper.getClassStruct();
Statement firstdata = findFirstData(root);
if (firstdata != null) {
while (!firstdata.getExprents().isEmpty()) {
Exprent exprent = firstdata.getExprents().get(0);
boolean found = false;
if (exprent.type == Exprent.EXPRENT_ASSIGNMENT) {
AssignmentExprent asexpr = (AssignmentExprent)exprent;
if (asexpr.getLeft().type == Exprent.EXPRENT_FIELD) {
FieldExprent fexpr = (FieldExprent)asexpr.getLeft();
if (fexpr.isStatic() && fexpr.getClassname().equals(cl.qualifiedName) &&
cl.hasField(fexpr.getName(), fexpr.getDescriptor().descriptorString)) {
if (isExprentIndependent(asexpr.getRight(), meth)) {
String keyField = InterpreterUtil.makeUniqueKey(fexpr.getName(), fexpr.getDescriptor().descriptorString);
if (!wrapper.getStaticFieldInitializers().containsKey(keyField)) {
wrapper.getStaticFieldInitializers().addWithKey(asexpr.getRight(), keyField);
firstdata.getExprents().remove(0);
found = true;
}
}
}
}
}
if (!found) {
break;
}
}
}
}
private static void extractDynamicInitializers(ClassWrapper wrapper) {
StructClass cl = wrapper.getClassStruct();
boolean isAnonymous = DecompilerContext.getClassProcessor().getMapRootClasses().get(cl.qualifiedName).type == ClassNode.CLASS_ANONYMOUS;
List<List<Exprent>> lstFirst = new ArrayList<List<Exprent>>();
List<MethodWrapper> lstMethWrappers = new ArrayList<MethodWrapper>();
for (MethodWrapper meth : wrapper.getMethods()) {
if ("<init>".equals(meth.methodStruct.getName()) && meth.root != null) { // successfully decompiled constructor
Statement firstdata = findFirstData(meth.root);
if (firstdata == null || firstdata.getExprents().isEmpty()) {
return;
}
lstFirst.add(firstdata.getExprents());
lstMethWrappers.add(meth);
Exprent exprent = firstdata.getExprents().get(0);
if (!isAnonymous) { // FIXME: doesn't make sense
if (exprent.type != Exprent.EXPRENT_INVOCATION ||
!isInvocationInitConstructor((InvocationExprent)exprent, meth, wrapper, false)) {
return;
}
}
}
}
if (lstFirst.isEmpty()) {
return;
}
while (true) {
String fieldWithDescr = null;
Exprent value = null;
for (int i = 0; i < lstFirst.size(); i++) {
List<Exprent> lst = lstFirst.get(i);
if (lst.size() < (isAnonymous ? 1 : 2)) {
return;
}
Exprent exprent = lst.get(isAnonymous ? 0 : 1);
boolean found = false;
if (exprent.type == Exprent.EXPRENT_ASSIGNMENT) {
AssignmentExprent asexpr = (AssignmentExprent)exprent;
if (asexpr.getLeft().type == Exprent.EXPRENT_FIELD) {
FieldExprent fexpr = (FieldExprent)asexpr.getLeft();
if (!fexpr.isStatic() && fexpr.getClassname().equals(cl.qualifiedName) &&
cl.hasField(fexpr.getName(), fexpr
.getDescriptor().descriptorString)) { // check for the physical existence of the field. Could be defined in a superclass.
if (isExprentIndependent(asexpr.getRight(), lstMethWrappers.get(i))) {
String fieldKey = InterpreterUtil.makeUniqueKey(fexpr.getName(), fexpr.getDescriptor().descriptorString);
if (fieldWithDescr == null) {
fieldWithDescr = fieldKey;
value = asexpr.getRight();
}
else {
if (!fieldWithDescr.equals(fieldKey) ||
!value.equals(asexpr.getRight())) {
return;
}
}
found = true;
}
}
}
}
if (!found) {
return;
}
}
if (!wrapper.getDynamicFieldInitializers().containsKey(fieldWithDescr)) {
wrapper.getDynamicFieldInitializers().addWithKey(value, fieldWithDescr);
for (List<Exprent> lst : lstFirst) {
lst.remove(isAnonymous ? 0 : 1);
}
}
else {
return;
}
}
}
private static boolean isExprentIndependent(Exprent exprent, MethodWrapper meth) {
List<Exprent> lst = exprent.getAllExprents(true);
lst.add(exprent);
for (Exprent expr : lst) {
switch (expr.type) {
case Exprent.EXPRENT_VAR:
VarVersionPaar varpaar = new VarVersionPaar((VarExprent)expr);
if (!meth.varproc.getExternvars().contains(varpaar)) {
String varname = meth.varproc.getVarName(varpaar);
if (!varname.equals("this") && !varname.endsWith(".this")) { // FIXME: remove direct comparison with strings
return false;
}
}
break;
case Exprent.EXPRENT_FIELD:
return false;
}
}
return true;
}
private static Statement findFirstData(Statement stat) {
if (stat.getExprents() != null) {
return stat;
}
else {
if (stat.isLabeled()) { // FIXME: Why??
return null;
}
switch (stat.type) {
case Statement.TYPE_SEQUENCE:
case Statement.TYPE_IF:
case Statement.TYPE_ROOT:
case Statement.TYPE_SWITCH:
case Statement.TYPE_SYNCRONIZED:
return findFirstData(stat.getFirst());
default:
return null;
}
}
}
private static boolean isInvocationInitConstructor(InvocationExprent inv, MethodWrapper meth, ClassWrapper wrapper, boolean withThis) {
if (inv.getFunctype() == InvocationExprent.TYP_INIT) {
if (inv.getInstance().type == Exprent.EXPRENT_VAR) {
VarExprent instvar = (VarExprent)inv.getInstance();
VarVersionPaar varpaar = new VarVersionPaar(instvar);
String classname = meth.varproc.getThisvars().get(varpaar);
if (classname != null) { // any this instance. TODO: Restrict to current class?
if (withThis || !wrapper.getClassStruct().qualifiedName.equals(inv.getClassname())) {
return true;
}
}
}
}
return false;
}
}