最近在复习,无聊就自学了会java,写了下面的代码,但是不知道为什么会出错...希望各位大牛解答下,谢谢啦..
import java.util.*;
public class Demo {public int fun(){
Scanner sc = new Scanner(System.in);
try {
int data= sc.nextInt();
return data;
} catch(Exception e) {
System.out.println("bad input!");
}
}/*出现错误的地方*
public static void main(String[] args){
Demo demo=new Demo();
int i,j,t;
int [] anArray;
anArray = new int[5];for(i=0;i<=4;i++){
anArray[i]=demo.fun();}
for(i=0;i<=4;i++){
for(j=0;j<=4;j++){
if(anArray[i]>anArray[j]){
t=anArray[i];
anArray[i]=anArray[j];
anArray[j]=t;}
}
}
for(i=0;i<=4;i++){
System.out.println(anArray[i]);}
}
}
import java.util.*;
public class Demo {public int fun(){
Scanner sc = new Scanner(System.in);
try {
int data= sc.nextInt();
return data;
} catch(Exception e) {
System.out.println("bad input!");
}
}/*出现错误的地方*
public static void main(String[] args){
Demo demo=new Demo();
int i,j,t;
int [] anArray;
anArray = new int[5];for(i=0;i<=4;i++){
anArray[i]=demo.fun();}
for(i=0;i<=4;i++){
for(j=0;j<=4;j++){
if(anArray[i]>anArray[j]){
t=anArray[i];
anArray[i]=anArray[j];
anArray[j]=t;}
}
}
for(i=0;i<=4;i++){
System.out.println(anArray[i]);}
}
}
Scanner sc = new Scanner(System.in);
try {
int data= sc.nextInt();
return data;
} catch(Exception e) {
System.out.println("bad input!");
}
}主要是没有返回值,如果产生异常了,就会没有返回值
public int fun(){
Scanner sc = new Scanner(System.in);
try {
int data= sc.nextInt();
return data;
} catch(Exception e) {
System.out.println("bad input!");
}
return -99999999;
}
Scanner sc = new Scanner(System.in);
try {
int data = sc.nextInt();
return data;
} catch (Exception e) {
System.out.println("bad input!");
}
}
fun方法必须要有一个返回值,当int data = sc.nextInt(); 发生异常的时候那么这个方法就没有返回值了。
import java.util.*;
public class Demo
{ public int fun()
{
Scanner sc = new Scanner(System.in);
try
{
int data= sc.nextInt();
return data;
} catch(Exception e)
{
System.out.println("bad input!");
}
//没有返回值
return 0;
//////
}
public static void main(String[] args)
{
Demo demo=new Demo();
int i,j,t;
int [] anArray;
anArray = new int[5]; for(i=0;i<=4;i++)
{
anArray[i]=demo.fun();}
for(i=0;i<=4;i++)
{
for(j=0;j<=4;j++)
{
if(anArray[i]>anArray[j])
{
t=anArray[i];
anArray[i]=anArray[j];
anArray[j]=t;
}
}
}
for(i=0;i<=4;i++)
{
System.out.println(anArray[i]);
}
}
}