import java.io.*;
public class sort { private static double num[];
private static String ss;
private static double newss;
private static int m=0;
private static BufferedReader br;
public static void main(String[] args) {
System.out.println("请输入数字,要结束输入请输入0000");
try{
br=new BufferedReader(new InputStreamReader(System.in));
ss=br.readLine();
newss=Double.parseDouble(ss);
}catch(IOException e)
{
e.printStackTrace();
}
do
{
try{
ss=br.readLine();
newss=Double.parseDouble(ss);
num[m]=newss;
m++;
}catch(IOException e)
{
e.printStackTrace();
}
}while(newss!=0000);
}}
语法没有错误,但为什么输入到第二个数字的时候 就会产生这么一个异常:
Exception in thread "main" java.lang.NullPointerException
at sort.main(sort.java:28)
public class sort { private static double num[];
private static String ss;
private static double newss;
private static int m=0;
private static BufferedReader br;
public static void main(String[] args) {
System.out.println("请输入数字,要结束输入请输入0000");
try{
br=new BufferedReader(new InputStreamReader(System.in));
ss=br.readLine();
newss=Double.parseDouble(ss);
}catch(IOException e)
{
e.printStackTrace();
}
do
{
try{
ss=br.readLine();
newss=Double.parseDouble(ss);
num[m]=newss;
m++;
}catch(IOException e)
{
e.printStackTrace();
}
}while(newss!=0000);
}}
语法没有错误,但为什么输入到第二个数字的时候 就会产生这么一个异常:
Exception in thread "main" java.lang.NullPointerException
at sort.main(sort.java:28)
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;public class sort
{
private static List<Double> numList = new ArrayList<Double>(); private static String ss; private static double newss; private static int m = 0; private static BufferedReader br; public static void main(String[] args)
{
System.out.println("请输入数字,要结束输入请输入0000");
try
{
br = new BufferedReader(new InputStreamReader(System.in));
ss = br.readLine();
newss = Double.parseDouble(ss); }
catch(IOException e)
{
e.printStackTrace();
} do
{
try
{
ss = br.readLine();
newss = Double.parseDouble(ss); numList.add(m, newss);
m++;
}
catch(IOException e)
{
e.printStackTrace();
}
}
while(newss != 0000);
}
}