Java/JNDI LDAP/Connection Pooling

how to enable connection pooling. Use debug option to observe connection usage

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import java.util.Hashtable;
import javax.naming.Context;
import javax.naming.NamingException;
import javax.naming.directory.DirContext;
import javax.naming.directory.InitialDirContext;
/**
 * Demonstrates how to enable connection pooling. Use debug option to observe
 * connection usage.
 * 
 * usage: java -Dcom.sun.jndi.ldap.connect.pool.debug=fine UsePool
 */
class UsePool {
  public static void main(String[] args) {
    // Set up environment for creating initial context
    Hashtable<String, Object> env = new Hashtable<String, Object>(11);
    env
        .put(Context.INITIAL_CONTEXT_FACTORY,
            "com.sun.jndi.ldap.LdapCtxFactory");
    env.put(Context.PROVIDER_URL, "ldap://localhost:389/o=JNDITutorial");
    // Enable connection pooling
    env.put("com.sun.jndi.ldap.connect.pool", "true");
    try {
      // Create one initial context (Get connection from pool)
      DirContext ctx = new InitialDirContext(env);
      System.out.println(ctx.getAttributes("ou=NewHires"));
      // do something useful with ctx
      // Close the context when we"re done
      ctx.close(); // Return connection to pool
      // Create another initial context (Get connection from pool)
      DirContext ctx2 = new InitialDirContext(env);
      System.out.println(ctx2.getAttributes("ou=People"));
      // do something useful with ctx2
      // Close the context when we"re done
      ctx2.close(); // Return connection to pool
    } catch (NamingException e) {
      e.printStackTrace();
    }
  }
}