如果下面这个异常发生了,
try{
in =new BufferedReader(new FileReader("TestMain.java"));
}catch(FileNotFoundException e){}
那么你下面in.readLine不就是没有初始化了吗!正确如下:
public class GetLineNum{
public static void main(String[] args){
int i;
BufferedReader in;
try{
in =new BufferedReader(new FileReader("TestMain.java"));
i = 0; while (in.readLine() != null){
i++;
}
}catch(IOException e){}
}catch(FileNotFoundException e){}
System.out.println("Line Number:" + i);
}
}
try{
in =new BufferedReader(new FileReader("TestMain.java"));
}catch(FileNotFoundException e){}
那么你下面in.readLine不就是没有初始化了吗!正确如下:
public class GetLineNum{
public static void main(String[] args){
int i;
BufferedReader in;
try{
in =new BufferedReader(new FileReader("TestMain.java"));
i = 0; while (in.readLine() != null){
i++;
}
}catch(IOException e){}
}catch(FileNotFoundException e){}
System.out.println("Line Number:" + i);
}
}
public static void main(String[] args){
int i;
BufferedReader in=null;//修改在这里
try{
in =new BufferedReader(new FileReader("TestMain.java"));
}catch(FileNotFoundException e){}
i = 0;
try{
while (in.readLine() != null){
i++;
}
}catch(IOException e){}
System.out.println("Line Number:" + i);
}
}
public static void main(String[] args){
int i;
BufferedReader in=null;//修改在这里
try{
in =new BufferedReader(new FileReader("TestMain.java"));
}catch(FileNotFoundException e){}
i = 0;
try{
while (in.readLine() != null){
i++;
}
}catch(IOException e){}
System.out.println("Line Number:" + i);
}
}