Example of BoxLayout in java.

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

class MyBoxLayout extends Frame
{
Button b[];

MyBoxLayout()
{
b=new Button[5];

for(int i=0;i<5;i++)
{
b[i]=new Button("Button "+ (i+1));
add(b[i]);
}
setLayout(new BoxLayout(this,BoxLayout.Y_AXIS));
setSize(300,300);
setVisible(true);
}
public static void main(String surat[])
{
new MyBoxLayout();
}
}

Output: