java异常类

package shb.java.exception;
/**
 * 测试异常类
 * @Package:shb.java.exception
 * @Description：
 * @author shaobn
 * @Date 2015-9-7上午11:52:42
 */
public class Demo_2 {
    public static void main(String[] args) {
        testTD_5();
    }
    public static void testTD_2(){
        TDemo_2 td_2 = new TDemo_2();
        try {
            td_2.getResult(9, 0);//一旦发生异常，函数中后面的方法不再执行即结束
            System.out.println("over");//发生异常后，此句已不能再执行。    直接抛出异常对象，由catch块中异常对象的引用来接收。
        } /*catch (Exception e) {
            // TODO: handle exception
            System.out.println(e.getMessage());
        }*///如果一开始就用Exception会覆盖子异常类，则会只执行Exception，其余都不能执行。
        catch (ArithmeticException ae) {
            // TODO: handle exception
            System.out.println(ae.getMessage());
            System.out.println("算术异常");
        }catch (ArrayIndexOutOfBoundsException aiobe) {
            // TODO: handle exception
            System.out.println(aiobe.getMessage());
            System.out.println("数组越界异常");
        }
        System.out.println("helloworld");
    }
    //自定义异常类
    public static void testTD_3(){
        TDemo_3 td_3 = new TDemo_3();
        try {
            td_3.getResult_3(9, 0);
            System.out.println("over");
        } catch (Exception e) {
            // TODO: handle exception            
            System.out.println(e.getMessage());
        }
        System.out.println("hellobeijing");
    }
    //自定义的继承RuntimeException类的异常（编译时是不报错的，运行时检查异常）
    public static void testTD_4(){
        
        TDemo_4 td_4 = new TDemo_4();
        td_4.getResult(9, 0);
    }
    public static void testTD_5(){
        TDemo_5 td_5 = new TDemo_5();
        try {
            td_5.testMethod();
        } catch (Exception e) {
            // TODO: handle exception
            System.out.println("异常已经处理");
        }
    }
}
class TDemo_2{
    private int age = 10;
    public int getAge(){
        return this.age;
    }
    //声明两个异常，算术异常，数组越界异常。
    public int getResult(int a,int b) throws ArithmeticException,
    ArrayIndexOutOfBoundsException{
        byte[] arr = new byte[a];
        b = a/b;
        arr[a] = 9;
        return a/b;
    }        
}
class TDemo_3{
    private int height = 90;
    public int getHeight(){
        return this.height;
    }
    public int getResult_3(int a,int b) throws TDemo_3Exception{
        if(b==0)
            //抛出自定义异常，必须在方法上声明异常类。
            throw new TDemo_3Exception("自定义的异常类");    
        return a/b;
    }
}
//编译时被检测的异常
class TDemo_3Exception extends Exception{
    public TDemo_3Exception(String str){
        super(str);        
    }
    //重写getMessage()方法
    public String getMessage(){
        return super.getMessage();
    }
    
}
//编译时不被检测的异常
class TDemo_4Exception extends RuntimeException{
    public TDemo_4Exception(String str){
        super(str);
    }
}
class TDemo_4{
    private int with = 90;
    public int getWith(){
        return this.with;
    }
    public int getResult(int a,int b){
        if(b==0)
            throw new TDemo_4Exception("自定义的runtime异常");
        return a/b;
        
    }
    public void testResult(int a,int b){
        if(b<0)
            throw new TDemo_4Exception("b小于0");
        System.out.println("测试成功");
    }
    
}
class TDemo_5Exception extends Exception{
    
    public TDemo_5Exception(String str){
        super(str);    
    }
    
}
class TDemo_5{
    public void testMethod() throws TDemo_5Exception{
        TDemo_4 td_4 = new TDemo_4();
        try {
            td_4.testResult(9, -1);
        } catch (Exception e) {
            // TODO: handle exception
            throw new TDemo_5Exception("处理失败");
        }
        
    }        
}