Comparing arrayList

[chanshaw]

Alright I need a little help here I want to compare to arraylists and if a match occurs return the value of whatever item matched as a string. Thanks alot.

[umbr]

Hi, chanshaw.
Just a simple sample :)

public static String findInList(List<Object> list, Object pattern)
{
    for(Object o : list)
        if(o.equals(pattent)
            return o.toString();

    return null;
}

Instead Object type you can use another one.

[chanshaw]

Ok that didn't really help but thanks here's my code

import java.sql.Statement;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.util.ArrayList;

/**
 * @date February 14, 2009
 * @author Colin Hanshaw
 */

public class ProcessChecker
{
    String parsedString;
    String test;
    int counter = 0;
    ArrayList parsedStrings = new ArrayList();
    ArrayList blockedApps = new ArrayList();
    private static String dbURL = "jdbc:derby://localhost:1527/MyDesk;user=administrator;password=password";
    Connection conn = null;
    boolean running = true;

    public static void main(String[] args) throws Exception
    {
        ProcessChecker checker = new ProcessChecker();
    }

    public ProcessChecker() throws Exception
    {
        createConnection();
        listRunningProcesses();
        quereyDatabase();
        tryFind();
    }

    private void createConnection()
    {
        try
        {
            Class.forName("org.apache.derby.jdbc.ClientDriver").newInstance();
            conn = DriverManager.getConnection(dbURL);
        }
        catch (Exception except)
        {
            except.printStackTrace();
        }
    }

    public void listRunningProcesses()
    {
        try
        {
            Runtime runtime = Runtime.getRuntime();
            String cmds[] = {"cmd", "/c", "tasklist"};
            Process proc = runtime.exec(cmds);
            InputStream inputstream = proc.getInputStream();
            InputStreamReader inputstreamreader = new InputStreamReader(inputstream);
            BufferedReader bufferedreader = new BufferedReader(inputstreamreader);
            String line;
            while ((line = bufferedreader.readLine()) != null)
            {
               parsedString = parseString(line);
               parsedStrings.add(new String(parsedString));
               counter++;
            }
            removeElements();
        }
        catch(Exception ex)
        {
            System.out.println("Tasklist might not exist");
        }
    }

    public String parseString(String incString)
    {
        String myParsedString = incString;
        String delims = "[ ]+";
        String[] tokens = incString.split(delims);
        myParsedString = tokens[0];
        return myParsedString;
    }

    public void removeElements()
    {
        parsedStrings.remove(0);
        parsedStrings.remove(0);
        parsedStrings.remove(0);
    }

    public void quereyDatabase() throws Exception
    {
       try
       {
           Statement stmt = conn.createStatement();
           ResultSet rs;
           rs = stmt.executeQuery("select BLOCKEDITEMS from ADMINISTRATOR.BLOCKEDLIST");
           while ( rs.next() )
           {
               String blockedItem = rs.getString("BLOCKEDITEMS");
               blockedApps.add(new String(blockedItem));
           }
           conn.close();
       }

       catch (Exception e)
       {
           System.err.println("Got an exception! ");
           System.err.println(e.getMessage());
       }
    }

    public void tryFind()
    {
        
    }
    

    
    /*public void endProcess()
    {
        if(line.startsWith(testString))
                {
                    runtime.exec("taskkill /IM " + testString);
                }
    }*/
}

So here's the arraylists

parsedStrings contains

String "Chris"
String "Nick"
String "Tom"
String "Melissa"
String "Wombat"

blockedApps contains

String "Tyler"
String "Chris"
String "Art"
String "Melissa"

I want the tryFind() method to compare the two arraylists

So it would return true for Chris
Then would return true for Melissa

Thanks hope that made more sence.

[JosAH]

Read the API docs for the List interface; it has a boolean contains() method; call that method for every element in the other list; or, if you want to go fancy, have a look at the retainAll() method.

kind regards,

Jos