JAVA 7新特性——在单个catch代码块中捕获多个异常，以及用升级版的类型检查重新抛出异常

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catch (IOException ex) {

     logger.error(ex);

     throw new MyException(ex.getMessage());

catch (SQLException ex) {

     logger.error(ex);

     throw new MyException(ex.getMessage());

}catch (Exception ex) {

     logger.error(ex);

     throw new MyException(ex.getMessage());

}

在Java 7中，我们可以用一个catch块捕获所有这些异常：

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catch(IOException | SQLException | Exception ex){

     logger.error(ex);

     throw new MyException(ex.getMessage());

}

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package com.journaldev.util;

public class Java7MultipleExceptions {

    public static void main(String[] args) {

        try{

            rethrow("abc");

        }catch(FirstException | SecondException | ThirdException e){

            //以下赋值将会在编译期抛出异常，因为e是final型的

            //e = new Exception();

            System.out.println(e.getMessage());

        }

    }

    static void rethrow(String s) throws FirstException, SecondException,

            ThirdException {

        try {

            if (s.equals("First"))

                throw new FirstException("First");

            else if (s.equals("Second"))

                throw new SecondException("Second");

            else

                throw new ThirdException("Third");

        } catch (Exception e) {

            //下面的赋值没有启用重新抛出异常的类型检查功能，这是Java 7的新特性

            // e=new ThirdException();

            throw e;

        }

    }

    static class FirstException extends Exception {

        public FirstException(String msg) {

            super(msg);

        }

    }

    static class SecondException extends Exception {

        public SecondException(String msg) {

            super(msg);

        }

    }

    static class ThirdException extends Exception {

        public ThirdException(String msg) {

            super(msg);

        }

    }

}