Java Swing: JSeparator, JTree

Java JSeparator

The object of JSeparator class is used to provide a general purpose component for implementing divider lines. It is used to draw a line to separate widgets in a Layout. It inherits JComponent class.

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JSeparator class declaration

1. public class JSeparator extends JComponent implements SwingConstants, Accessible  

Commonly used Constructors of JSeparator

Constructor	Description
JSeparator()	Creates a new horizontal separator.
JSeparator(int orientation)	Creates a new separator with the specified horizontal or vertical orientation.

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Commonly used Methods of JSeparator

Method	Description
void setOrientation(int orientation)	It is used to set the orientation of the separator.
int getOrientation()	It is used to return the orientation of the separator.

Java JSeparator Example 1

1. import javax.swing.*;    
2. class SeparatorExample    
3. {    
4.           JMenu menu, submenu;    
5.           JMenuItem i1, i2, i3, i4, i5;    
6.           SeparatorExample()  {    
7.           JFrame f= new JFrame("Separator Example");    
8.           JMenuBar mb=new JMenuBar();    
9.           menu=new JMenu("Menu");    
10.           i1=new JMenuItem("Item 1");    
11.           i2=new JMenuItem("Item 2");       
12.           menu.add(i1);  
13.           menu.addSeparator();  
14.           menu.add(i2);  
15.           mb.add(menu);    
16.           f.setJMenuBar(mb);    
17.           f.setSize(400,400);    
18.           f.setLayout(null);    
19.           f.setVisible(true);    
20. }    
21. public static void main(String args[])    
22. {    
23. new SeparatorExample();    
24. }}    

Output:

Java JSeparator Example 2

1. import javax.swing.*;    
2. import java.awt.*;  
3. public class SeparatorExample    
4. {    
5.     public static void main(String args[]) {  
6.         JFrame f = new JFrame("Separator Example");      
7.         f.setLayout(new GridLayout(0, 1));  
8.         JLabel l1 = new JLabel("Above Separator");  
9.         f.add(l1);  
10.         JSeparator sep = new JSeparator();  
11.         f.add(sep);  
12.         JLabel l2 = new JLabel("Below Separator");  
13.         f.add(l2);  
14.         f.setSize(400, 100);  
15.         f.setVisible(true);  
16.       }  
17.     }    

Output:

Java JProgressBar

The JProgressBar class is used to display the progress of the task. It inherits JComponent class.

JProgressBar class declaration

Let's see the declaration for javax.swing.JProgressBar class.

1. public class JProgressBar extends JComponent implements SwingConstants, Accessible  

Commonly used Constructors:

Constructor	Description
JProgressBar()	It is used to create a horizontal progress bar but no string text.
JProgressBar(int min, int max)	It is used to create a horizontal progress bar with the specified minimum and maximum value.
JProgressBar(int orient)	It is used to create a progress bar with the specified orientation, it can be either Vertical or Horizontal by using SwingConstants.VERTICAL and SwingConstants.HORIZONTAL constants.
JProgressBar(int orient, int min, int max)	It is used to create a progress bar with the specified orientation, minimum and maximum value.

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Commonly used Methods:

Method	Description
void setStringPainted(boolean b)	It is used to determine whether string should be displayed.
void setString(String s)	It is used to set value to the progress string.
void setOrientation(int orientation)	It is used to set the orientation, it may be either vertical or horizontal by using SwingConstants.VERTICAL and SwingConstants.HORIZONTAL constants.
void setValue(int value)	It is used to set the current value on the progress bar.

Java JProgressBar Example

1. import javax.swing.*;    
2. public class ProgressBarExample extends JFrame{    
3. JProgressBar jb;    
4. int i=0,num=0;     
5. ProgressBarExample(){    
6. jb=new JProgressBar(0,2000);    
7. jb.setBounds(40,40,160,30);         
8. jb.setValue(0);    
9. jb.setStringPainted(true);    
10. add(jb);    
11. setSize(250,150);    
12. setLayout(null);    
13. }    
14. public void iterate(){    
15. while(i<=2000){    
16.   jb.setValue(i);    
17.   i=i+20;    
18.   try{Thread.sleep(150);}catch(Exception e){}    
19. }    
20. }    
21. public static void main(String[] args) {    
22.     ProgressBarExample m=new ProgressBarExample();    
23.     m.setVisible(true);    
24.     m.iterate();    
25. }    
26. }    

Output:

Java JTree

The JTree class is used to display the tree structured data or hierarchical data. JTree is a complex component. It has a 'root node' at the top most which is a parent for all nodes in the tree. It inherits JComponent class.

JTree class declaration

Let's see the declaration for javax.swing.JTree class.

1. public class JTree extends JComponent implements Scrollable, Accessible  

Commonly used Constructors:

Constructor	Description
JTree()	Creates a JTree with a sample model.
JTree(Object[] value)	Creates a JTree with every element of the specified array as the child of a new root node.
JTree(TreeNode root)	Creates a JTree with the specified TreeNode as its root, which displays the root node.

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Java JTree Example

1. import javax.swing.*;  
2. import javax.swing.tree.DefaultMutableTreeNode;  
3. public class TreeExample {  
4. JFrame f;  
5. TreeExample(){  
6.     f=new JFrame();   
7.     DefaultMutableTreeNode style=new DefaultMutableTreeNode("Style");  
8.     DefaultMutableTreeNode color=new DefaultMutableTreeNode("color");  
9.     DefaultMutableTreeNode font=new DefaultMutableTreeNode("font");  
10.     style.add(color);  
11.     style.add(font);  
12.     DefaultMutableTreeNode red=new DefaultMutableTreeNode("red");  
13.     DefaultMutableTreeNode blue=new DefaultMutableTreeNode("blue");  
14.     DefaultMutableTreeNode black=new DefaultMutableTreeNode("black");  
15.     DefaultMutableTreeNode green=new DefaultMutableTreeNode("green");  
16.     color.add(red); color.add(blue); color.add(black); color.add(green);      
17.     JTree jt=new JTree(style);  
18.     f.add(jt);  
19.     f.setSize(200,200);  
20.     f.setVisible(true);  
21. }  
22. public static void main(String[] args) {  
23.     new TreeExample();  
24. }}  

Output:

Anurag Rana Educator CSE/IT