create a program that will extract particular records from a file

[acev]

Hi All

I am trying to create a program that will extract particular records from a file. The file is delimited by |.

The working copy should enable this

C:\>java match "-t|" -4 -f Harvey -10 -f Atlanta callbook.txt

"-t|" - denotes a delimiter
-4 - denotes the field number
-f - case sensitive

Thanks

[Nicholas Jordan]

There is a common tool implemented in java called regular expressions.
java.util.regex (Java 2 Platform SE v1.4.2)

java.util.regex.Pattern.compile("-t|\\w{0,4} ..... and so on ....");// much work omitted

To address individual fields in a line we would use a line reader, from which the returned line may be plaeced in an array using String.split(" ");

case sensitive is the default.

This only a partal solution, others will likely add to it.

[acev]

Hi

Thanks for your response.
This is what I have done so far:

 import  java.io.*;
import java.util.*;

public class assess1
{
    static public void main(String args[])
    {
        int[] totals = new int[10];
        try
        {
            BufferedReader inFile = new BufferedReader(new FileReader(args[0]) ); 
            try
            {
                String line;
		String StrSearch = "HARVEY";
		int counter = 0;

                boolean foundIt = false;

                while((line = inFile.readLine()) != null)
                {
        	    // search for the string
			
  	           String[] values = line.split("\\|");
        
                   for (String str : values) {
			if (str.equals("HARVEY", CASE_SENSITIVE)) {
                 		System.out.println(line);
        	  		System.out.println();
				counter++;
                         }
		   }

                }

		if (counter == 0) {
                 		
			System.out.println("String not found");
		}
                
		inFile.close();
            }
            catch(IOException e)
            {
                System.err.println("IO exception");
                System.exit(1);
            }
            catch(NumberFormatException e)
            {
                System.err.println("Value " + e.getMessage() + "not numeric");
            }
        }
        catch(FileNotFoundException e)
        {
            System.err.println( "Couldn't open " + e.getMessage() );
            System.exit(1);
        }

    }
}

Note the search string is hard coded and none of the other criterias have been implemented I am struggling.

This code below I tried to use for reading the arguments from command line.

import  java.io.*;
import java.util.*;

public class check1
{
    static public void main(String args[])
    {
        // Check if a command line argument exists
        if(args.length == 0)
            System.exit(0);
            
        // Loop through the command line arguments

	String sSeperator;
	String sPosition;
	String sCase;
	String sTranspo;
	String sDiffer;
	String filename;
	String strSerach;
	String vArgs;	

        for(int counter = 0; counter < args.length; counter++){
		
	    vArgs = args[counter];

	    if (vArgs.substring(1,2) = "-t") {
		sSeperator = vArgs;
	    }
	    

	    if (vArgs.equals("-f")){
		
		sCase = vArgs;
	    }

	    if (vArgs.substring(vArgs.length -3, 3) = "txt") {
		
		filename = vArgs;
	    }

            System.out.println("argument index : " + vArgs);   
            System.out.println();
            System.out.println(" first : " + sSeperator);    
            System.out.println(" Second : " + sPosition);    
            System.out.println(" third : " + sCase);    
            System.out.println(" fourth : " + sTranspo);    
            System.out.println(" fifth : " + sDiffer);    
            System.out.println(" sixth : " + filename); 
            System.out.println(" seventh : " + strsearch); 
		
        }
    }
}

I would really appreciate it if you could tell me what I can do to solve this.

Acev

[Norm]

Comments on several parts of your program:

   if(args.length == 0)
            System.exit(0);

Put out an error message so user will know what happened.

 if (vArgs.substring(1,2) = "-t") {

What about the leading "?

Use if( ) { ...}else if( ) {...} vs separate if statements. Otherwise all the ifs will be executed. It may be true that more than one if is true, but if not, chain the ifs with elses.

what I can do to solve this.

Write the code to solve the problem. Compile and test it. If the output is wrong, copy and paste it here and describe what's wrong with it and how you want it to look. Also comment the code to describe your logic and what it is you are trying to do so that someone reading the code can understand what you are trying to do. Most of us can see what the code is actually doing, but we don't know what you are trying to do.

[acev]

Hi

Thanks for your reply my question is how do I extract 2 different search criterias and use them to search the file? I have taken the If else if syntax on board I will change the code. Please advise.

[Norm]

how do I extract 2 different search criterias

Extract from where?
An example might help. Show the source and what you want extracted from it.