closurecomparator.java

来自「Groovy动态语言 运行在JVM中的动态语言 可以方便的处理业务逻辑变化大的业」· Java 代码 · 共 71 行

/*
 $Id: ClosureComparator.java 4098 2006-10-10 16:09:48Z blackdrag $

 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.

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package groovy.util;

import groovy.lang.Closure;
import java.util.Comparator;
import org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation;

/**
 * A Comparator which uses a closure to compare 2 values being equal
 * 
 * @author <a href="mailto:[e-mail]">James Strachan</a>
 * @version $Revision: 4098 $
 */
public class ClosureComparator implements Comparator {

    Closure closure;

    public ClosureComparator(Closure closure) {
        this.closure = closure;
    }

    public int compare(Object object1, Object object2) {
        Object value = closure.call(new Object[] {object1, object2});
        return DefaultTypeTransformation.intUnbox(value);
    }
}