Java中的自定义异常

自定义异常有两种，分别是继承Exception和Throwable 类,因为Throwable是exception的父类，所以，继承Exception和继承Throwable效果差不多，下面是继承Exception的自定义的类的实现和用法。package com.cvicse.exception;

1、自定义异常

/**

 *

 * @功能 自定义异常 ObjAlreadyExistException

 * @author 创建人 gao_jie

 * @date 创建日期 Jul 3, 2008

 * @version 1.0

 *

 */

public class ObjAlreadyExistException extends Exception {

    private static final long serialVersionUID = 1L;

    /**

     * Constructs a new exception with <code>null</code> as its detail

     * message. The cause is not initialized, and may subsequently be

     * initialized by a call to {@link #initCause}.

     */

    public ObjAlreadyExistException() {

       super();

    }

    /**

     * @param message

     *            the detail message. The detail message is saved for later

     *            retrieval by the {@link #getMessage()} method.

     */

    public ObjAlreadyExistException(String message) {

       super(message);

    }

    /**

     * @param message

     *            the detail message (which is saved for later retrieval by the

     *            {@link #getMessage()} method).

     * @param cause

     *            the cause (which is saved for later retrieval by the

     *            {@link #getCause()} method). (A <tt>null</tt> value is

     *            permitted, and indicates that the cause is nonexistent or

     *            unknown.)

     * @since 1.4

     */

    public ObjAlreadyExistException(String message, Throwable cause) {

       super(message, cause);

    }

    /**

     * @param cause

     *            the cause (which is saved for later retrieval by the

     *            {@link #getCause()} method). (A <tt>null</tt> value is

     *            permitted, and indicates that the cause is nonexistent or

     *            unknown.)

     * @since 1.4

     */

    public ObjAlreadyExistException(Throwable cause) {

       super(cause);

    }

}

 

2、在函数中应用自己的异常

package com.cvicse.service;

 

import com.cvicse.exception.ObjAlreadyExistException;

 

/**

    *

    * @功能；定义一个实现类，它应用了自定义的异常

    * @author 创建人 gao_jie

    * @date 创建日期 Jul 3, 2008

    * @version 1.0

    *

    */

public class CaculateFunction {

 

    /**

     * 计算函数中的加函数

     * @param a

     * @param b

     * @throws ObjAlreadyExistException

     */

    public void add(float a, float b) throws ObjAlreadyExistException {

       if (a == b)

           throw new ObjAlreadyExistException("输入的数相等！");

    }

}

3、在主函数中调用该函数

package com.cvicse.mian;

 

import com.cvicse.exception.ObjAlreadyExistException;

import com.cvicse.service.CaculateFunction;

 

/**

 *

 * @功能

 * @author 创建人 gao_jie

 * @date 创建日期 Jul 3, 2008

 * @version 1.0

 *

 */

public class Application {

 

    private static CaculateFunction CaculateFunction = null;

 

    /**

     * @param args

     */

    public static void main(String[] args) {

       // TODO Auto-generated method stub

       CaculateFunction = new CaculateFunction();

       try {

           CaculateFunction.add(12, 12);

       } catch (ObjAlreadyExistException e) {

           // TODO Auto-generated catch block

           e.printStackTrace();

       }

    }

}

评论

1 楼 birthcat 2011-11-04