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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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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.
/** * 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
/** * 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()"
/** * 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.
/** * 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
/** * 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
/** * 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
/** * 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
/** * Code */
public void codeValue(Environment env, Context ctx, Assembler asm) { asm.add(where, opc_aload, field.number); }
Print
/** * Print */
public void print(PrintStream out) { if (outerArg != null) { out.print("(outer="); outerArg.print(out); out.print(" "); } String pfx = (field == null) ? "" : field.getClassDefinition().getName().getFlatName().getName()+"."; pfx += opNames[op]; out.print(pfx + "#" + ((field != null) ? field.hashCode() : 0)); if (outerArg != null) out.print(")"); } }