operatorselectionmodel.java

Enjoy Web Dev With Tapestry 一书的源代码

package com.ttdev.tddcalc;

import java.util.*;

import org.apache.tapestry.form.*;

public class OperatorSelectionModel implements IPropertySelectionModel {
	private List operators;
	
	public OperatorSelectionModel() {
		operators = new ArrayList();
		operators.add(new Add());
		operators.add(new Minus());
		operators.add(new Multiply());
		operators.add(new Divide());
	}
	public int getOptionCount() {
		return operators.size();
	}

	public Object getOption(int index) {
		return getOperator(index);
	}
	public String getLabel(int index) {
		return getOperator(index).getName();
	}

	public String getValue(int index) {
		return Integer.toString(index);
	}

	public Object translateValue(String value) {
		return getOperator(Integer.parseInt(value));
	}
	public Operator getOperator(int index) {
		return (Operator) operators.get(index);
	}

}