lucee.transformer.bytecode.statement.ForEach.java Source code

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Here is the source code for lucee.transformer.bytecode.statement.ForEach.java

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/**
 *
 * Copyright (c) 2014, the Railo Company Ltd. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either 
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public 
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 * 
 **/
package lucee.transformer.bytecode.statement;

import lucee.runtime.util.ForEachUtil;
import lucee.transformer.bytecode.Body;
import lucee.transformer.bytecode.BytecodeContext;
import lucee.transformer.bytecode.BytecodeException;
import lucee.transformer.bytecode.Position;
import lucee.transformer.bytecode.expression.Expression;
import lucee.transformer.bytecode.expression.var.Variable;
import lucee.transformer.bytecode.expression.var.VariableRef;
import lucee.transformer.bytecode.util.ExpressionUtil;
import lucee.transformer.bytecode.util.Types;
import lucee.transformer.bytecode.visitor.OnFinally;
import lucee.transformer.bytecode.visitor.TryFinallyVisitor;

import org.objectweb.asm.Label;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.commons.GeneratorAdapter;
import org.objectweb.asm.commons.Method;

public final class ForEach extends StatementBase implements FlowControlBreak, FlowControlContinue, HasBody {

    private Body body;
    private VariableRef key;
    private Expression value;

    private final static Method HAS_NEXT = new Method("hasNext", Types.BOOLEAN_VALUE, new Type[] {});
    private final static Method NEXT = new Method("next", Types.OBJECT, new Type[] {});
    private final static Method SET = new Method("set", Types.OBJECT,
            new Type[] { Types.PAGE_CONTEXT, Types.OBJECT });
    public static final Method TO_ITERATOR = new Method("toIterator", Types.ITERATOR, new Type[] { Types.OBJECT });
    private static final Type FOR_EACH_UTIL = Type.getType(ForEachUtil.class);
    protected static final Method RESET = new Method("reset", Types.VOID, new Type[] { Types.ITERATOR });

    //private static final Type COLLECTION_UTIL = Type.getType(CollectionUtil.class);

    private Label begin = new Label();
    private Label end = new Label();
    private FlowControlFinal fcf;
    private String label;

    /**
     * Constructor of the class
     * @param key
     * @param value
     * @param body
     * @param line
     */
    public ForEach(Variable key, Expression value, Body body, Position start, Position end, String label) {
        super(start, end);
        this.key = new VariableRef(key);
        this.value = value;
        this.body = body;
        this.label = label;
        body.setParent(this);

    }

    @Override
    public void _writeOut(BytecodeContext bc) throws BytecodeException {
        GeneratorAdapter adapter = bc.getAdapter();
        final int it = adapter.newLocal(Types.ITERATOR);
        final int item = adapter.newLocal(Types.REFERENCE);

        //Value
        // ForEachUtil.toIterator(value)
        value.writeOut(bc, Expression.MODE_REF);
        adapter.invokeStatic(FOR_EACH_UTIL, TO_ITERATOR);
        //adapter.invokeStatic(COLLECTION_UTIL, TO_ITERATOR);
        // Iterator it=...
        adapter.storeLocal(it);
        TryFinallyVisitor tfv = new TryFinallyVisitor(new OnFinally() {

            @Override
            public void _writeOut(BytecodeContext bc) throws BytecodeException {
                GeneratorAdapter a = bc.getAdapter();
                //if(fcf!=null && fcf.getAfterFinalGOTOLabel()!=null)ASMUtil.visitLabel(a,fcf.getFinalEntryLabel());
                a.loadLocal(it);
                a.invokeStatic(FOR_EACH_UTIL, RESET);
                /*if(fcf!=null){
                   Label l=fcf.getAfterFinalGOTOLabel();
                   if(l!=null)a.visitJumpInsn(Opcodes.GOTO, l);
                }*/
            }
        }, getFlowControlFinal());
        tfv.visitTryBegin(bc);
        // Key
        // new VariableReference(...)
        key.writeOut(bc, Expression.MODE_REF);
        // VariableReference item=...
        adapter.storeLocal(item);

        // while
        ExpressionUtil.visitLine(bc, getStart());
        adapter.visitLabel(begin);

        // hasNext
        adapter.loadLocal(it);
        adapter.invokeInterface(Types.ITERATOR, HAS_NEXT);
        adapter.ifZCmp(Opcodes.IFEQ, end);

        // item.set(pc,it.next());
        adapter.loadLocal(item);
        adapter.loadArg(0);
        adapter.loadLocal(it);
        adapter.invokeInterface(Types.ITERATOR, NEXT);
        adapter.invokeInterface(Types.REFERENCE, SET);
        adapter.pop();

        // Body
        body.writeOut(bc);
        adapter.visitJumpInsn(Opcodes.GOTO, begin);
        adapter.visitLabel(end);
        tfv.visitTryEnd(bc);

    }

    @Override
    public Label getBreakLabel() {
        return end;
    }

    @Override
    public Label getContinueLabel() {
        return begin;
    }

    @Override
    public Body getBody() {
        return body;
    }

    @Override
    public FlowControlFinal getFlowControlFinal() {
        if (fcf == null)
            fcf = new FlowControlFinalImpl();
        return fcf;
    }

    @Override
    public String getLabel() {
        return label;
    }
}