java try catch
来源:互联网 发布:淘宝卖家评论 编辑:程序博客网 时间:2024/05/24 05:08
public class AAA {
public static void main(String[] args) {
System.out.println("=============test0==================");
System.out.println(test0());
System.out.println("===============================");
System.out.println("=============test0_1==================");
System.out.println(test0_1());
System.out.println("===============================");
System.out.println("=============test0_2==================");
System.out.println(test0_2());
System.out.println("===============================");
System.out.println("=============test1==================");
System.out.println(test1());
System.out.println("===============================");
System.out.println("=============test1_1==================");
System.out.println(test1_1());
System.out.println("===============================");
System.out.println("\n============test2===================");
System.out.println(test2());
System.out.println("===============================");
System.out.println("\n============test2_1===================");
System.out.println(test2_1());
System.out.println("===============================");
System.out.println("\n============test3===================");
System.out.println(test3());
System.out.println("===============================");
System.out.println("\n============test3_1===================");
System.out.println(test3_1());
System.out.println("===============================");
}
public static String test0() {
String a;
int b=0;
try{
b = 8/0; //(1) ------0不能当被除数,此行出现异常,try里面的return不会执行
return "try"; //=========================没有执行======================================
}catch(Exception e){
e.printStackTrace();//(2) //此时程序不会终止,还会继续往下执行
}
a = String.valueOf(b); //(3)
return a+b; //(4)
}
//try和catch中都有了return
public static String test0_1() {
String a;
int b;
try{
b = 8/0; //(1) 0不能当被除数,此行出现异常,try里面的return不会执行
a = String.valueOf(b); //===================不执行
return a+b; //===================不执行
}catch(Exception e){
e.printStackTrace(); //(2)
return "test0_1 出错了"; //(3)
}
// String s="zhaohao"; //try和catch中都有了return,此处加 任何东西 会报错 --------不让加,报错
// System.out.println("哈哈 ,赵皓"); //try和catch中都有了return,此处加 任何东西 会报错 --------不让加,报错
//return a+b; //try和catch中都有了return,此处加return会报错 --------不让加,报错
}
public static String test0_2() {
String a;
int b=0;
try{
b = 8/0;
}catch(Exception e){
b=100;
}
a = String.valueOf(b); //会执行此处=====================
return a; //会执行此处=====================
}
public static int test1() {
int m = 3;
int n = 2;
int a = 7;
int b = 8;
int s =0;
try{
s=m+n; //(1)
return s; //(2)先执行这个===(此时s的值已经确认,finally并不会修改它),====再执行finally ===================(5)结束了,此时才会真正的返回该值
} catch ( Exception e ) {
} finally {
//对int的更改均无效
s=a+b; //(3)
System.out.println("do finally 哈哈"); //(4)
}
return s; //==============不会执行===========
}
//执行结果:
// do finally 哈哈
// 5
public static String test1_1() {
String a = "in try中";
try{
return a;
} catch ( Exception e ) {
} finally { //从eclpise报警告可看出,finally里面不建议有return语句
a = "in finally中的return的值";
System.out.println("test1_1 中的 do finally");
return a; //注释掉这句,eclipse将不再警告
}
}
//返回结果:
//test1_1 中的 do finally
//in finally中的return的值
public static int test2() {
int a = 1;
try{
return a;
} catch ( Exception e ) {
} finally {
a = 2;
System.out.println("do finally");
}
return a;
} //很显然,finally里面更改无效,返回的是a=1
public static int test2_1() {
int a = 1;
try{
return a;
} catch ( Exception e ) {
} finally {
a = 2;
System.out.println("do finally");
return a;
}
} //很显然,a取finally里面的值,a=2
//Helper类,将整数转换成字符串
static class Helper {
int a;
public String toString() {
return String.valueOf(a);
}
}
public static Helper test3() {
Helper h = new Helper();
h.a = 1;
try{
return h;
} catch ( Exception e ) {
} finally {
h.a = 2; //对h.a的更改起作用!!
//因为在try里面返回的是一个句柄,它指向的对象的内容 是可以改变的
System.out.println("do finally");
}
return h; //这个不会被执行
}
public static Helper test3_1() {
Helper h = new Helper();
h.a = 1;
try{
return h;
} catch ( Exception e ) {
} finally {
h.a = 2; //返回a=2,这个不用说了
System.out.println("do finally");
return h;
}
}
/**
* 总结:
* return语句,finally里面不建议放return语句,根据需要,可以放在try和catch里面
*
*/
}
public static void main(String[] args) {
System.out.println("=============test0==================");
System.out.println(test0());
System.out.println("===============================");
System.out.println("=============test0_1==================");
System.out.println(test0_1());
System.out.println("===============================");
System.out.println("=============test0_2==================");
System.out.println(test0_2());
System.out.println("===============================");
System.out.println("=============test1==================");
System.out.println(test1());
System.out.println("===============================");
System.out.println("=============test1_1==================");
System.out.println(test1_1());
System.out.println("===============================");
System.out.println("\n============test2===================");
System.out.println(test2());
System.out.println("===============================");
System.out.println("\n============test2_1===================");
System.out.println(test2_1());
System.out.println("===============================");
System.out.println("\n============test3===================");
System.out.println(test3());
System.out.println("===============================");
System.out.println("\n============test3_1===================");
System.out.println(test3_1());
System.out.println("===============================");
}
public static String test0() {
String a;
int b=0;
try{
b = 8/0; //(1) ------0不能当被除数,此行出现异常,try里面的return不会执行
return "try"; //=========================没有执行======================================
}catch(Exception e){
e.printStackTrace();//(2) //此时程序不会终止,还会继续往下执行
}
a = String.valueOf(b); //(3)
return a+b; //(4)
}
//try和catch中都有了return
public static String test0_1() {
String a;
int b;
try{
b = 8/0; //(1) 0不能当被除数,此行出现异常,try里面的return不会执行
a = String.valueOf(b); //===================不执行
return a+b; //===================不执行
}catch(Exception e){
e.printStackTrace(); //(2)
return "test0_1 出错了"; //(3)
}
// String s="zhaohao"; //try和catch中都有了return,此处加 任何东西 会报错 --------不让加,报错
// System.out.println("哈哈 ,赵皓"); //try和catch中都有了return,此处加 任何东西 会报错 --------不让加,报错
//return a+b; //try和catch中都有了return,此处加return会报错 --------不让加,报错
}
public static String test0_2() {
String a;
int b=0;
try{
b = 8/0;
}catch(Exception e){
b=100;
}
a = String.valueOf(b); //会执行此处=====================
return a; //会执行此处=====================
}
public static int test1() {
int m = 3;
int n = 2;
int a = 7;
int b = 8;
int s =0;
try{
s=m+n; //(1)
return s; //(2)先执行这个===(此时s的值已经确认,finally并不会修改它),====再执行finally ===================(5)结束了,此时才会真正的返回该值
} catch ( Exception e ) {
} finally {
//对int的更改均无效
s=a+b; //(3)
System.out.println("do finally 哈哈"); //(4)
}
return s; //==============不会执行===========
}
//执行结果:
// do finally 哈哈
// 5
public static String test1_1() {
String a = "in try中";
try{
return a;
} catch ( Exception e ) {
} finally { //从eclpise报警告可看出,finally里面不建议有return语句
a = "in finally中的return的值";
System.out.println("test1_1 中的 do finally");
return a; //注释掉这句,eclipse将不再警告
}
}
//返回结果:
//test1_1 中的 do finally
//in finally中的return的值
public static int test2() {
int a = 1;
try{
return a;
} catch ( Exception e ) {
} finally {
a = 2;
System.out.println("do finally");
}
return a;
} //很显然,finally里面更改无效,返回的是a=1
public static int test2_1() {
int a = 1;
try{
return a;
} catch ( Exception e ) {
} finally {
a = 2;
System.out.println("do finally");
return a;
}
} //很显然,a取finally里面的值,a=2
//Helper类,将整数转换成字符串
static class Helper {
int a;
public String toString() {
return String.valueOf(a);
}
}
public static Helper test3() {
Helper h = new Helper();
h.a = 1;
try{
return h;
} catch ( Exception e ) {
} finally {
h.a = 2; //对h.a的更改起作用!!
//因为在try里面返回的是一个句柄,它指向的对象的内容 是可以改变的
System.out.println("do finally");
}
return h; //这个不会被执行
}
public static Helper test3_1() {
Helper h = new Helper();
h.a = 1;
try{
return h;
} catch ( Exception e ) {
} finally {
h.a = 2; //返回a=2,这个不用说了
System.out.println("do finally");
return h;
}
}
/**
* 总结:
* return语句,finally里面不建议放return语句,根据需要,可以放在try和catch里面
*
*/
}
0 0
- java---try ---catch--finally
- JAVA try&&catch
- JAVA 异常 try-catch
- java try catch
- Java try catch
- java try catch finally
- java try catch
- java try catch
- Java: try catch finally
- JAVA异常try{}catch
- java-try...catch...finally
- java try-catch-finally
- java try没有catch
- Java 异常 try catch
- JAVA异常处理try...catch
- java 7中再谈try catch
- java throw throws try catch
- Java中的try catch finally
- servlet复习(六)Session管理
- List<T>排序,java和c#都用得到
- 机房合作验收总结
- XML读写之DOM
- LeetCode刷题: Odd Even Linked List
- java try catch
- 深度学习硬件指南(号称最全)
- C# 的List<T>筛选数据填充到另一个List<T>
- 30分钟groovy快速入门并掌握(ubuntu 14.04+IntelliJ 13) - Hi_Amos
- RHEL 6.5 x64bit下expect命令的安装
- ubundu操作提示
- 网络通信基本原理
- Using Covering Indexes to Improve Query Performance
- RSS订阅