Java中的自定义异常捕获方式

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class /*自定义异常类名*/ extends Exception
{
 public /*自定义异常类名*/  //相当于重写其构造函数{
  super("/*输出的信息*/");
 }
}

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try
{
 //有可能出现异常的代码；
}
catch(Exception e)//将异常捕获，放进类e中
{
 //对异常进行处理
}finally{ //最后处理完后执行的代码
}

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public static int StringtoInt(String s) throws TooLong,ZeroLength,InvalidChar

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{
  int len,i,ans=0;
  boolean flag=true;
  len=s.length();
  for (i=0;i<=len-1;i++)
  {
   if (s.charAt(i)<'0'||s.charAt(i)>'9')
   {
    flag=false;
    break;
   }
  }
  if (s.length()>=6)
  {
   throw new TooLong();//遇到异常抛出
  }
  else if (s.length()==0)
  {
   throw new ZeroLength();
  }
  else if (flag==false)
  {
   throw new InvalidChar();
  }
  for (i=0;i<=len-1;i++)
  {
   ans=ans+(s.charAt(i)-'0')*((int)Math.pow(10,len-i-1));
  }
  return ans;
 }

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import java.util.*;
 
class InvalidChar extends Exception
{
 public InvalidChar()
 {
  super("字符串中含有非法字符，无法转换为整型");
 }
}
 
class TooLong extends Exception
{
 public TooLong()
 {
  super("字符串长度过长，无法转换成整型");
 }
}
 
class ZeroLength extends Exception
{
 public ZeroLength()
 {
  super("长度是零，无法转换成整型");
 }
} 
 
public class ExceptionTester
{
 public static int StringtoInt(String s) throws TooLong,ZeroLength,InvalidChar
 {
  int len,i,ans=0;
  boolean flag=true;
  len=s.length();
  for (i=0;i<=len-1;i++)
  {
   if (s.charAt(i)<'0'||s.charAt(i)>'9')
   {
    flag=false;
    break;
   }
  }
  if (s.length()>=6)
  {
   throw new TooLong();
  }
  else if (s.length()==0)
  {
   throw new ZeroLength();
  }
  else if (flag==false)
  {
   throw new InvalidChar();
  }
  for (i=0;i<=len-1;i++)
  {
   ans=ans+(s.charAt(i)-'0')*((int)Math.pow(10,len-i-1));
  }
  return ans;
 }
 public static void main(String args[])
 {
  int a;
  String s;
  Scanner cin=new Scanner(System.in);
  System.out.println("输入一个字符串");
  s=cin.nextLine();
  try
  {
   a=StringtoInt(s);
  }
  catch(Exception e)
  {
   System.out.println(e.toString());
   return;
  }
  System.out.println(a+"n"+"没有异常被捕获");
  return;
 }
}

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package com.cestbon.exception;
public class RpcException extends Exception {
/**
* 
*/
private static final long serialVersionUID = 6554142484920002283L;
}