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Scala重写Java可变参数方法问题
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‎Scala_Java_Override_Variable_Parameter/README.md‎

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### Scala重写Java可变参数方法问题 ###
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```Java
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public interface KeyGenerator {
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/**
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* Generate a key for the given method and its parameters.
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* @param target the target instance
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* @param method the method being called
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* @param params the method parameters (with any var-args expanded)
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* @return a generated key
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*/
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Object generate(Object target, Method method, Object... params);
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}
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```
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如以上的Java接口，Java中的可变参数是以...出现，而Scala则不同，Scala的可变参数是以*出现的，如下：
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```Scala
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def generate(target:Object, method: Method, params: Object*): Object = {
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//省略
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}
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```
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如果你使用IDE自动生成的方法参数如下：
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```Scala
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def generate(target:Any, method: Method, params: Array[AnyRef]): Object = {
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//省略
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}
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```
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在使用Scala重写了KeyGenerator接口的generate方法时编译器总是无法通过，即在Scala中使用params: Object*或者是Array[AnyRef]是无法替代Object... params的，注意Scala中的Any和AnyRef都是Object类型，classOf[Any]和classOf[AnyRef]都是Object类型,解决办法是你只需要将Array[AnyRef]修改成AnyRef*就可以编译通过了。
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```Scala
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def wiselyKeyGenerator(): KeyGenerator = {
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new KeyGenerator() {
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override protected def generate(target: Any, method: Method, params: AnyRef*): Object = {
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var sb = new StringBuilder()
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sb.append(target.getClass().getName())
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sb.append(method.getName())
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for(param <- params) {
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sb.append(param.toString())
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}
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sb.toString()
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}
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};
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}
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```

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