Question

I want to read a data stream and everytime it reads a certain word or phrase I want the count to go up. The example I have below fails to count it. I tried looking for “echo percent” as well. All the bat file does is echo percent.

try { 
    String ls_str;
    String percent = "percent";
    Process ls_proc = Runtime.getRuntime().exec("c:\\temp\\percenttest.bat"); 
    // get its output (your input) stream    
    DataInputStream ls_in = new DataInputStream(ls_proc.getInputStream()); 
    while ((ls_str = ls_in.readLine()) != null ) { 
        System.out.println(ls_str);
        progressBar.setValue(progress);
        taskOutput.append(String.format(ls_str+"\n", progress));
        if (ls_str == percent)  {
            progress++;   
        } 
    }
} catch (IOException e1) { 
    System.out.println(e1.toString());                 
    e1.printStackTrace();
}

setProgress(Math.min(progress, 100));   

Answer 1

Don’t compare the Strings with ==, use the equals method.

If you compare the Strings with ==, you’re checking to see if they’re the same String.

If you compare them with equals, you’re checking whether or not their contents are the same.

Instead of:

if (ls_str == percent)

Do this:

if (ls_str.equals(percent))

If you want to ignore case, you can do it like this:

if (ls_str.equalsIgnoreCase(percent))

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EDIT

Your String format is also messed up.

Change:

taskOutput.append(String.format(
ls_str+"\n", progress));

to:

taskOutput.append(String.format(
ls_str+"\n"), progress);

Notice the parentheses change.

---

Take a look at these for more explanations:

Java String.equals versus ==

http://www.java-samples.com/showtutorial.php?tutorialid=221