动手动脑一:
代码:
import javax.swing.*;
class AboutException {
public static void main(String[] a)
{
int i=1, j=0, k;//double可以被0整除,整数和浮点型运算不一样
k=i/j;
try
{
k = i/j; // Causes division-by-zero exception
//throw new Exception("Hello.Exception!");
}
catch ( ArithmeticException e)
{
System.out.println("被0除. "+ e.getMessage());
}
catch (Exception e)
{
if (e instanceof ArithmeticException)
System.out.println("被0除");
else
{
System.out.println(e.getMessage());
}
}
finally
{
JOptionPane.showConfirmDialog(null,"OK"+k);
}
}
}
结论:
Try{
//可能发生运行错误的代码;
}
catch(异常类型 异常对象引用){
//用于处理异常的代码
}
finally{
//用于“善后” 的代码
}
动手动脑二:
截图:
动手动脑三:
截图:
动手动脑四:
代码:
public class EmbededFinally {
public static void main(String args[]) {
int result;
try {
System.out.println("in Level 1");
try {
System.out.println("in Level 2");
// result=100/0; //Level 2
try {
System.out.println("in Level 3");
result=100/0; //Level 3
}
catch (Exception e) {
System.out.println("Level 3:" + e.getClass().toString());
}
finally {
System.out.println("In Level 3 finally");
}
// result=100/0; //Level 2
}
catch (Exception e) {
System.out.println("Level 2:" + e.getClass().toString());
}
finally {
System.out.println("In Level 2 finally");
}
// result = 100 / 0; //level 1
}
catch (Exception e) {
System.out.println("Level 1:" + e.getClass().toString());
}
finally {
System.out.println("In Level 1 finally");
}
}
}
截图:
总结:在一个方法体中finally执行的是相对应的catch的内容
动手动脑五:
代码:
public class SystemExitAndFinally {
public static void main(String[] args)
{
try{
System.out.println("in main");
throw new Exception("Exception is thrown in main");
//System.exit(0);
}
catch(Exception e)
{
System.out.println(e.getMessage());
System.exit(0);
}
finally
{
System.out.println("in finally");
}
}
}
截图:
总结:当catch中有exit退出程序时,这时就不在执行finally