searching for a word in a text file in java blue j

Question

When i run the code it gives an error

java.lang.ArrayIndexOutOfBoundsException: 0
    at SearchFile.main(SearchFile.java:28)

MyNote.txt is the text file saved in D directory of my computer. whereas "ad" is the word in that text file.

import java.io.*;

public class SearchFile {

public static void main(String args[]) {

args[0] = "ad";

if (args.length > 0) {
String searchword = args[0];

try {

int LineCount = 0;
String line = "";

BufferedReader bReader = new BufferedReader(new FileReader("D:/MyNote.txt"));

while ((line = bReader.readLine()) != null) {
LineCount++;

int posFound = line.indexOf(searchword);
if (posFound > - 1) {
System.out.println("Search word found at position " + posFound + " on line " + LineCount);
}
}
bReader.close();
}
catch (IOException e) {
System.out.println("Error: " + e.toString());
}
}
else {
System.out.println("Please provide a word to search the file for.");
}
}
}

i dont know what the error is or what i have done wrong. i am new to this actually please help!! THANK YOU

You are assigning a value to args[0] without checking to see if there is even such an index to set. In other words, if there are no arguments that have been given to the main method then args[0] will throws an `ArrayIndexOutOfBoundsException` as there is no such array index. — Rabbit Guy, Apr 18 '16 at 15:18

score 0 · Answer 1 · answered Apr 18 '16 at 15:19

The problem is that your args[] is empty and has no size when your application starts. In this case there exists no index 0 and your line with args[0] = "ad"; fails.

Try to start your application with an argument instead of trying to set it manually in the code. If you do not see any other solution create an array yourself and set it as the variable filled with the information you want to use.

Nikolas Charalambidis · Accepted Answer · 2016-04-18T15:26:40.080

0

Use the another variable instead than args[0]:

String str = "ad";
if (str.length() > 0) {
String searchword = str;

The variable args[0] is used as an input to the class through the main method. Moreover it's empty in your case because no arguments were given.

edited Apr 18 '16 at 15:26

answered Apr 18 '16 at 15:21

Nikolas Charalambidis

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thank you man so much – newbieee Apr 18 '16 at 15:29
actually the code that you're seeing above is not written by me that is why i was'nt able o edit the code properly – newbieee Apr 18 '16 at 15:31
Glad it helps :) Yea, working with someone's else piece of code is suffering sometimes. – Nikolas Charalambidis Apr 18 '16 at 15:37
you're a big help bro .. hey how do i add you as a friend man !! – newbieee Apr 18 '16 at 15:58
bro i have another task on my hand .. – newbieee Apr 18 '16 at 15:59
i used scanner class so that the user can input the word to be searched... – newbieee Apr 18 '16 at 16:01
now if the user enters a word that is not present in the text file ... the program should add that word in the end of that text file and display a message that "The word you entered was not present so i have added that word to my dictionary." – newbieee Apr 18 '16 at 16:03
Look up here at the site and try to do it yourself first. If you will not be able to find a solution, feel free to ask a new question. Keywords: `Java write to File` and `Java String`. – Nikolas Charalambidis Apr 18 '16 at 16:11

searching for a word in a text file in java blue j

2 Answers2