Java:try与finally

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任何调用try 或者catch中的return语句之前，都会先执行finally语句，当然前提是finally存在。如果finally中有return语句，那么程序就return了，所以finally中的return是一定会被return的，编译器把finally中的return实现为一个warning。

例一

package exercise;/** * 基本类型测试try,finally * @author Administrator **/public class TestReturnAndFinally {    public static void main(String[] args) {        // TODO Auto-generated method stub        System.out.println(new TestReturnAndFinally().test());;    }    static int test() {        int x = 1;        try {            return x;        }        finally {            ++x;        }    }}

结果：
1

例二

package exercise;/** * 引用类型测试try,finally * @author Administrator **/public class TestReturnAndFinally3 {    public static void main(String[] args) {        // TODO Auto-generated method stub        System.out.println(new TestReturnAndFinally3().test());;    }    static StringBuffer test() {        StringBuffer a = new StringBuffer("init");        try {            a.append(" try");            return a;        }        finally {            a.append(" finally");        }    }}

结果：
init try finally

例三

package exercise;/** * 普通类 * @author Administrator **/public class Quote {public int a = 1;}package exercise;/** * 引用类型中的基本类型测试try,finally * @author Administrator **/public class TestReturnAndFinally2 {    public static void main(String[] args) {        // TODO Auto-generated method stub        System.out.println(new TestReturnAndFinally2().test().a);;    }    static Quote test() {        Quote q = new Quote();        try {            return q;        }        finally {            q.a++;        }    }}

结果：
2

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