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

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Here is the source code for lucee.transformer.bytecode.statement.For.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.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.literal.LitBoolean;
import lucee.transformer.bytecode.util.ASMUtil;
import lucee.transformer.bytecode.util.ExpressionUtil;

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

public final class For extends StatementBaseNoFinal implements FlowControlBreak, FlowControlContinue, HasBody {

    private Expression init;
    private Expression condition;
    private Expression update;
    private Body body;

    //private static final int I=1;

    Label beforeUpdate = new Label();
    Label end = new Label();
    private String label;

    /**
     * Constructor of the class
     * @param init
     * @param condition
     * @param update
     * @param body
     * @param line
     */
    public For(Expression init, Expression condition, Expression update, Body body, Position start, Position end,
            String label) {
        super(start, end);
        this.init = init;
        this.condition = condition;
        this.update = update;
        this.body = body;
        this.label = label;
        body.setParent(this);

    }

    @Override
    public void _writeOut(BytecodeContext bc) throws BytecodeException {
        GeneratorAdapter adapter = bc.getAdapter();
        Label beforeInit = new Label();
        Label afterInit = new Label();
        Label afterUpdate = new Label();

        ExpressionUtil.visitLine(bc, getStart());
        adapter.visitLabel(beforeInit);
        if (init != null) {
            init.writeOut(bc, Expression.MODE_VALUE);
            adapter.pop();
        }
        adapter.visitJumpInsn(Opcodes.GOTO, afterUpdate);
        adapter.visitLabel(afterInit);

        body.writeOut(bc);

        adapter.visitLabel(beforeUpdate);
        //ExpressionUtil.visitLine(bc, getStartLine());
        if (update != null) {
            update.writeOut(bc, Expression.MODE_VALUE);
            ASMUtil.pop(adapter, update, Expression.MODE_VALUE);
        }
        //ExpressionUtil.visitLine(bc, getStartLine());
        adapter.visitLabel(afterUpdate);

        if (condition != null)
            condition.writeOut(bc, Expression.MODE_VALUE);
        else
            LitBoolean.TRUE.writeOut(bc, Expression.MODE_VALUE);
        adapter.visitJumpInsn(Opcodes.IFNE, afterInit);
        //ExpressionUtil.visitLine(bc, getEndLine());
        adapter.visitLabel(end);

    }

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

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

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

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