java通过抛异常来返回提示信息

最新推荐文章于 2024-08-26 12:05:31 发布

转载最新推荐文章于 2024-08-26 12:05:31 发布 · 890 阅读

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CC 4.0 BY-SA版权

原文链接：https://yq.aliyun.com/articles/270844

文章标签：

#java #前端 #后端 #ViewUI

本文介绍如何在Java中通过不同构造函数创建自定义异常，并展示如何使用这些构造函数来传递异常信息，包括直接传递消息字符串、将一个异常作为另一个异常的原因等。

结论：
如果把通过抛异常的方式得到提示信息，可以使用java.lang.Throwable中的构造函数：

    public Throwable(String message) {
        fillInStackTrace();
        detailMessage = message;
    }

或

    public Throwable(String message, Throwable cause) {
        fillInStackTrace();
        detailMessage = message;
        this.cause = cause;
    }

原因及代码示例：
1、通过java.lang.Throwable中的Constructs

    public Throwable(Throwable cause) {
        fillInStackTrace();
        detailMessage = (cause==null ? null : cause.toString());
        this.cause = cause;
    }

在输出时获取的detailMessage是：

exception.ProcessorException: java.lang.IllegalArgumentException: Failt to process

Exception信息的输出：

exception.ProcessorException: exception.ProcessorException: java.lang.IllegalArgumentException: Failt to process

code:

package exception;

/*2015-8-22*/
public class ExceptionChain {
    public static void main(String[] args) {
        Business business = new Business();
        try {
            business.doBusiness();
        } catch (ProcessorException e) {
            System.out.println(e.getMessage());
            System.out.println("e:\n" + e);
        }

    }

}

class Business {

    public void doBusiness() throws ProcessorException {

        try {
            process1();
        } catch (Exception e) {
            throw new ProcessorException(e);
            // throw new ProcessorException(e.getMessage(), e);
            // throw new ProcessorException(e.getMessage());
        }

    }

    private void process1() throws ProcessorException {
        try {
            process2();
        } catch (Exception e) {
            // throw new ProcessorException(e.getMessage(), e);
            // throw new ProcessorException(e.getMessage());
            throw new ProcessorException(e);
        }

    }

    private void process2() {
        throw new IllegalArgumentException("Failt to process");
    }

}

class ProcessorException extends Exception {

    private static final long serialVersionUID = -4270191862690602942L;

    public ProcessorException(Throwable cause) {
        super(cause);
    }

    public ProcessorException(String message) {
        super(message);
    }

    public ProcessorException(String message, Throwable cause) {
        super(message, cause);
    }

}

2、通过java.lang.Throwable中的Constructs

    public Throwable(String message) {
        fillInStackTrace();
        detailMessage = message;
    }

    /**
     * Fills in the execution stack trace. This method records within this
     * <code>Throwable</code> object information about the current state of
     * the stack frames for the current thread.
     *
     * @return  a reference to this <code>Throwable</code> instance.
     * @see     java.lang.Throwable#printStackTrace()
     */
    public synchronized native Throwable fillInStackTrace();

在输出时获取的detailMessage是：

Failt to process

Exception信息的输出：

exception.ProcessorException: Failt to process

code:
把上面示例代码中throw new ProcessorException(e.getMessage());注释去掉，把 // throw new ProcessorException(e);注释

3、通过java.lang.Throwable中的Constructs：

    public Throwable(String message, Throwable cause) {
        fillInStackTrace();
        detailMessage = message;
        this.cause = cause;
    }

在输出时获取的detailMessage是：

Failt to process

Exception信息的输出：

exception.ProcessorException: Failt to process

code:
操作方式与2相同