/*
* Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.tools.tree;
import sun.tools.java.*;
import sun.tools.asm.Assembler;
import java.io.PrintStream;
import java.util.Hashtable;
/**
* WARNING: The contents of this source file are not part of any
* supported API. Code that depends on them does so at its own risk:
* they are subject to change or removal without notice.
*/
public
class ThisExpression extends Expression {
LocalMember field;
Expression implementation;
Expression outerArg;
/**
* Constructor
*/
public ThisExpression(long where) {
super(THIS, where, Type.tObject);
}
protected ThisExpression(int op, long where) {
super(op, where, Type.tObject);
}
public ThisExpression(long where, LocalMember field) {
super(THIS, where, Type.tObject);
this.field = field;
field.readcount++;
}
public ThisExpression(long where, Context ctx) {
super(THIS, where, Type.tObject);
field = ctx.getLocalField(idThis);
field.readcount++;
}
/**
* Constructor for "x.this()"
*/
public ThisExpression(long where, Expression outerArg) {
this(where);
this.outerArg = outerArg;
}
public Expression getImplementation() {
if (implementation != null)
return implementation;
return this;
}
/**
* From the 'this' in an expression of the form outer.this(...),
* or the 'super' in an expression of the form outer.super(...),
* return the "outer" expression, or null if there is none.
*/
public Expression getOuterArg() {
return outerArg;
}
/**
* Check expression
*/
public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable<Object, Object> exp) {
if (ctx.field.isStatic()) {
env.error(where, "undef.var", opNames[op]);
type = Type.tError;
return vset;
}
if (field == null) {
field = ctx.getLocalField(idThis);
field.readcount++;
}
if (field.scopeNumber < ctx.frameNumber) {
// get a "this$C" copy via the current object
implementation = ctx.makeReference(env, field);
}
if (!vset.testVar(field.number)) {
env.error(where, "access.inst.before.super", opNames[op]);
}
if (field == null) {
type = ctx.field.getClassDeclaration().getType();
} else {
type = field.getType();
}
return vset;
}
public boolean isNonNull() {
return true;
}
// A 'ThisExpression' node can never appear on the LHS of an assignment in a correct
// program, but handle this case anyhow to provide a safe error recovery.
public FieldUpdater getAssigner(Environment env, Context ctx) {
return null;
}
public FieldUpdater getUpdater(Environment env, Context ctx) {
return null;
}
/**
* Inline
*/
public Expression inlineValue(Environment env, Context ctx) {
if (implementation != null)
return implementation.inlineValue(env, ctx);
if (field != null && field.isInlineable(env, false)) {
Expression e = (Expression)field.getValue(env);
//System.out.println("INLINE = "+ e + ", THIS");
if (e != null) {
e = e.copyInline(ctx);
e.type = type; // in case op==SUPER
return e;
}
}
return this;
}
/**
* Create a copy of the expression for method inlining
*/
public Expression copyInline(Context ctx) {
if (implementation != null)
return implementation.copyInline(ctx);
ThisExpression e = (ThisExpression)clone();
if (field == null) {
// The expression is copied into the context of a method
e.field = ctx.getLocalField(idThis);
e.field.readcount++;
} else {
e.field = field.getCurrentInlineCopy(ctx);
}
if (outerArg != null) {
e.outerArg = outerArg.copyInline(ctx);
}
return e;
}
/**
* Code
*/
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