[DonCash]

You need something like this:

Code:

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.InputStreamReader;
import java.io.Writer;

public class StringFind {
	
	public static String path;
	public static String FindMe;
	public String strLine;
	
	public void openFile(){

		String newLine = System.getProperty("line.separator");
		
		try {
			Writer output = new BufferedWriter(new FileWriter("output.txt"));
			
			FileInputStream in = new FileInputStream(path);
			BufferedReader br = new BufferedReader(new InputStreamReader(in));
		
		while ((strLine = br.readLine()) != null){
			
			if (strLine.contains(FindMe))	{
				output.write(strLine);
				output.write(newLine);
			}

			}
				output.close();
				System.out.println("Completed. Output file generated.");
				
		}catch(Exception e)	{
			System.out.println("OUCH! I fell over.");
			System.exit(0);
		}
	}

	public static void main(String[] args) {
		
		StringFind sf = new StringFind();

		if (args.length < 2){
			System.out.println("ERROR! No parameters sent");
			System.exit(0);
		}
		
                        //path = "myFile.txt";
		//FindMe = "10-10-2008";

		path = args[0];
		FindMe = args[1];
		
		sf.openFile();
				
	}
}

This code takes 2 parameters. The first is the file path eg: myfile.txt and the second is the string you are looking for.

As it reads the file it will write all the lines that match FindMe to the output.txt file.