SourceDefinedFunction.java

/*
Copyright (c) 2008 Arno Haase, Andr� Arnold.
All rights reserved. This program and the accompanying materials
are made available under the terms of the Eclipse Public License v1.0
which accompanies this distribution, and is available at
http://www.eclipse.org/legal/epl-v10.html

Contributors:
    Arno Haase - initial API and implementation
    Andr� Arnold
 */
package org.eclipse.xtend.backend.functions;

import java.util.List;

import org.eclipse.xtend.backend.common.BackendType;
import org.eclipse.xtend.backend.common.ExecutionContext;
import org.eclipse.xtend.backend.common.ExpressionBase;
import org.eclipse.xtend.backend.common.LocalVarContext;
import org.eclipse.xtend.backend.common.QualifiedName;
import org.eclipse.xtend.backend.common.StacktraceEntry;


/**
 * 
 * @author Arno Haase (http://www.haase-consulting.com)
 * @author Andr� Arnold
 */
public final class SourceDefinedFunction extends AbstractFunction {
    private final QualifiedName _name;
    private final List<String> _paramNames;
    private final ExpressionBase _def;

    public SourceDefinedFunction (QualifiedName name, List<String> paramNames, List<BackendType> paramTypes, BackendType returnType, ExpressionBase def, boolean cached, ExpressionBase guard) {
        super (guard, paramTypes, returnType, cached);
        _name = name;
        _paramNames = paramNames;
        _def = def;
    }

	public Object invoke (ExecutionContext ctx, Object[] params) {
        final LocalVarContext lvc = new LocalVarContext ();
        for (int i=0; i<_paramNames.size(); i++) {
            lvc.getLocalVars().put(_paramNames.get(i), params[i]);
        }
        
        final LocalVarContext oldLvc = ctx.getLocalVarContext();
        try {
            ctx.setLocalVarContext(lvc);
            
            if (ctx.isLogStacktrace())
                ctx.getStacktrace().add (new StacktraceEntry (_def.getPos(), ctx));
            
            return _def.evaluate(ctx);
        }
        finally {
            if (ctx.isLogStacktrace())
                ctx.getStacktrace().remove (ctx.getStacktrace().size() - 1);
            
            ctx.setLocalVarContext(oldLvc);
        }
    }

    public QualifiedName getName () {
        return _name;
    }
    
    public List<String> getParamNames() {
    	return _paramNames;
    }

    public ExpressionBase getDefExpression() {
		return _def;
	}
    
    @Override
    public String toString () {
        return "SourceDefinedFunction '" + _name + "' " + getParameterTypes();
    }
}