方法throws异常是一种粗颗粒的处理异常的方式,一但遇到异常,程序将会抛出异常停止运行,异常后面的代码将不会执行.
要想更细致的处理异可以用try catch方式.
public static void main(String[] args) throws FileNotFoundException {
// TODO Auto-generated method
System.out.println("1");
FileInputStream in = new FileInputStream("IoStreamTest.java");
System.out.println("2");
}
运行结果:
1
Exception in thread "main" java.io.FileNotFoundException: IoStreamTest.java (系统找不到指定的文件。)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(FileInputStream.java:106)
at java.io.FileInputStream.<init>(FileInputStream.java:66)
at IoStreamTest.IoStreamTest.main(IoStreamTest.java:16)
这种粗颗粒的处理方式,将会导致程序中断,和后面的代码不能执行.这种情况是我们不想看到的.
采用更细致的方式:
*/
public static void main(String[] args) {
// TODO Auto-generated method
System.out.println("1");
try {
FileInputStream in = new FileInputStream("IoStreamTest.java");
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
System.out.println("遇到异常");
e.printStackTrace();
}
System.out.println("2");
}
运行结果:
1
遇到异常
java.io.FileNotFoundException: IoStreamTest.java (系统找不到指定的文件。)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(FileInputStream.java:106)
at java.io.FileInputStream.<init>(FileInputStream.java:66)
at IoStreamTest.IoStreamTest.main(IoStreamTest.java:17)
2