NodeShuffler/src/processor/StackFrame.java

package processor;

import java.util.HashMap;

/**
 * a frame containing variables.
 * can be used for storing variables and/or for pushing them to the stack.
 * @author kolja
 *
 */
public class StackFrame {

    /**
     * whether the frame belongs to a function or a loop.
     * @author kolja
     *
     */
	public enum FrameType {
		FUNCTION,
		LOOP
	}
	
    private HashMap< String, Object > data;
    private FrameType type;
    
    public StackFrame( FrameType type )
    {
    	this.type = type;
        data = new HashMap< String, Object >();
    }
    
    public FrameType getType()
    {
    	return type;
    }
    
    public <T> void declare( String name, T value )
    {
        if( data.containsKey( name ) )
            throw new IllegalStateException( "Variable is already declared" );
        data.put( name, (Object)value );
    }
    
    public <T> void set( String name, T value )
    {
        data.put( name, (Object)value );
    }
    
    public void undeclare( String name )
    {
        data.remove( name );
    }
    
    public boolean isDefined( String name )
    {
        return data.containsKey( name );
    }
    
    @SuppressWarnings("unchecked")
    public <T> T get( String name )
    {
        return (T)data.get( name );
    }
}