[hardwired]

Works okay now: all components show up and remain visible.

Code:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Welcome extends JFrame
{
    JTextArea txt=new JTextArea("Welcome");
    JTextArea txt1=new JTextArea("Hello");
    JButton enter=new JButton(" Enter ");
    JLabel label_image1=new JLabel(); 
    JLabel label_image2=new JLabel(); 

    JPanel jp=(JPanel)this.getContentPane();

    public static void main(String args[])
    {
        new Welcome();
    }

    public Welcome()
    {
//        setExtendedState(getExtendedState() | Frame.MAXIMIZED_BOTH);
        label_image1.setIcon(new ImageIcon(//"a4.jpg"));
                                           "images/Bird.gif"));
        label_image2.setIcon(new ImageIcon(//"a5.jpg"));
                                           "images/Rabbit.gif"));

        jp.setLayout(null); 
//        jp.setBackground(new Color(0,0,0));

//        enter.setForeground(new Color(0,255,255));
        txt.setForeground(new Color(255,0,0));
        txt1.setForeground(new Color(255,0,0));

//        enter.setBackground(new Color(0,0,255));
//        txt.setBackground(new Color(0,0,0));
//        txt1.setBackground(new Color(0,0,0));

        enter.setFont(new Font("Cooper Black",Font.PLAIN, 30));
        txt.setFont(new Font("Courier", Font.BOLD, 48));
        txt1.setFont(new Font("Courier", Font.BOLD, 20));

        enter.setBounds(430,450,150,50);  // ) <-- errant brace
        txt.setBounds(300,100,400,200);
        txt1.setBounds(300,350,500,100);
        Dimension d = label_image1.getPreferredSize();
        label_image1.setBounds(//50,50,100,200);
                               50,50,d.width,d.height);
        d = label_image2.getPreferredSize();
        label_image2.setBounds(//600,550,100,200);  // was offscreen
                               50,350,d.width,d.height);

//        enter.setBorder(BorderFactory.createLineBorder(Color.red, 10));
        txt.setEditable(false);
        txt1.setEditable(false);

        jp.add(enter);
        jp.add(txt);
        jp.add(txt1);
        jp.add(label_image1);
        jp.add(label_image2);

        setSize(800,600);
        setLocation(100,100);
        // Always call this method last.
        setVisible(true);
    }
}