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String getMessage() //返回Throwable的详细消息字符串
String getLocalizedMessage() //返回Throwable的本地化描述
String toString() //返回此Throwable的简短描述
void printStackTrace()//将此Throwable及其追踪输出至标准错误流
void pritnStackTrace(PrintStream) //将此Throwable及其追踪输出到指定的输出流
void printStackTrace(java.io.PrintWriter) //将此Throwable及其追踪输出到指定的PrintWriter

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package exception;
//方法被覆盖时，只能抛出在基类方法的异常说明里列出来的那些异常。 
class BaseballException extends Exception {}
class Foul extends BaseballException {}
class Strike extends BaseballException {}

abstract class Inning {
public Inning() throws BaseballException {}
public void event() throws BaseballException {
}
public abstract void atBat() throws Strike, Foul;
public void walk() {} 
}

class StormException extends Exception {}
class RainedOut extends StormException {}
class PopFoul extends Foul {}

interface Storm {
public void event() throws RainedOut;
public void rainHard() throws RainedOut;
}

public class StormyInning extends Inning implements Storm {
//异常限制对构造器不起作用，可以为构造器添加新的异常，但是派生类构造器的异常说明必须包含基类构造器的异常说明
//派生类构造器不能捕获基类构造器抛出的异常
public StormyInning()
 throws RainedOut, BaseballException {}
public StormyInning(String s)
 throws Foul, BaseballException {}
  //基类方法未抛出异常，所以导出类不能抛出异常
 //void walk() throws PopFoul {} //Compile error
//接口不能为现存的来自基类的方法增加异常
//! public void event() throws RainedOut {}
public void rainHard() throws RainedOut {}
//可以不抛出任何异常，即使基类中定义了异常
public void event() {} 
// Overridden methods can throw inherited exceptions:
//重载的方法可以抛出继承的异常
public void atBat() throws PopFoul {}
public static void main(String[] args) {
 try {//仅捕获这个类所抛出的异常
   StormyInning si = new StormyInning();
   si.atBat();
 } catch(PopFoul e) {
   System.out.println("Pop foul");
 } catch(RainedOut e) {
   System.out.println("Rained out");
 } catch(BaseballException e) {
   System.out.println("Generic baseball exception");
 }

 try {
   // 向上转型
   Inning i = new StormyInning();
   i.atBat();
   //必须捕获来自基类方法的异常
 } catch(Strike e) {
   System.out.println("Strike");
 } catch(Foul e) {
   System.out.println("Foul");
 } catch(RainedOut e) {
   System.out.println("Rained out");
 } catch(BaseballException e) {
   System.out.println("Generic baseball exception");
 }
}
}