Null pointer when Reading text file in java

Question

I got Null pointer exception when reading data from file.if its returning a junk value how to handle that. if i didn't give trim giving some junk value. My code is:

BufferedReader br = null;
try {           
    String sCurrentval = "";
    br = new BufferedReader(new FileReader("filepath"));
    while ((sCurrentval = br.readLine()) != null) {
        System.out.println("Reading from File "+sCurrentval);
    }
    if(sCurrentval != null){
        sCurrentval = sCurrentval.trim();
    }
    System.out.println("outside :  Reading from File "+sCurrentval);
    if(sCurrentval != null && !sCurrentval.equalsIgnorecase("")){
        try{
            val = Integer.parseInt(sCurrentval.trim());
        }catch(Exception e){
            e.printStackTrace();
        }
    }else{
        System.out.println("Reading Value  null ");
    }
} catch (IOException e) {
    e.printStackTrace();
} finally {
    try {
        if (br != null)br.close();
    } catch (IOException ex) {
        ex.printStackTrace();
    }
}

Which line is giving the NullPointerException? You should be able to see that in the stacktrace. — S.L. Barth is on codidact.com
– S.L. Barth is on codidact.com, Commented Aug 27, 2013 at 9:47
The while will skip over the whole file. sCurrentval can only be null afterwards — Henry
– Henry, Commented Aug 27, 2013 at 10:01

newuser · Accepted Answer · 2013-08-27 10:38:24Z

Your BufferedReader br = null; with in the try. But your finally also using the same variable br.

 try
    {
    //
    BufferedReader br = null; // declared with in try
    //
    }
    finally {
    try {
    if (br != null) // In this line the br is not identified 
     br.close();
    } catch (IOException ex) 
    {
    ex.printStackTrace();
    }

Try to declare the BufferReader outside the try

BufferedReader br = null;

And then your while loop is only for the printing the value of the variable. Include the below if else condition within the while and then try the below code.

while ((sCurrentval = br.readLine()) != null)
            {
                System.out.println("Reading from File " + sCurrentval);
                if (sCurrentval != null && !sCurrentval.trim().isEmpty())
                {
                    try
                    {
                        val = Integer.parseInt(sCurrentval.trim());
                    }
                    catch (Exception e)
                    {
                        e.printStackTrace();
                    }
                }
                else
                {
                    System.out.println("Reading Value  null ");
                }
            }

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