FULL PRODUCT VERSION :
java version "1.8.0_101"
java <TM> SE Runtime Environment (build 1.8.0_101-b13)
Java Hotspot(TM) 64-bit Server VM (build 25.101-b13, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows 7 Professional (64-bit)

[Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
Button btnReset;

btnReset.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
txtName.setText("");
txtRollNo.setText("");
txtMarks.setText("");
}
});

In the above code setText("") method doesn't change the value of the Textfiled string to empty string.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
In the following program pressing the Reset button doesn't reset the Strings in textboxes.

import java.awt.*;
import java.awt.event.*;
import java.io.*;
      
class Ideone extends Frame
{
Label lblName, lblRollNo, lblMarks;
TextField txtName, txtRollNo, txtMarks;
Button btnReset, btnSave;

Ideone()
{
setLayout(new GridLayout(4, 2));
setTitle("Student Record Maintainer");
setSize(280,300);
setVisible(true);

lblName = new Label("Name: ");
txtName = new TextField("", 20);

lblRollNo = new Label("Roll No.: ");
txtRollNo = new TextField("", 20);

lblMarks = new Label("Marks: ");
txtMarks = new TextField("", 20);

btnReset = new Button("Reset");
btnSave = new Button("Save");

btnReset.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
txtName.setText("");
txtRollNo.setText("");
txtMarks.setText("");
}
});

btnSave.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent ae){
System.out.println(txtName.getText());
System.out.println(txtRollNo.getText());
System.out.println(txtMarks.getText());
}
});

addWindowListener( new WindowAdapter() {
public void windowClosing(WindowEvent we) {
System.exit(0);
}
}
);

add(lblName); add(txtName);
add(lblRollNo); add(txtRollNo);
add(lblMarks); add(txtMarks);
add(btnReset); add(btnSave);
    }
      
    public static void main(String args[]) throws java.lang.Exception
{
new Ideone();
    }
}


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Upon pressing the Reset button the textfields (i.e. Roll No, Name, Marks)
should be reset.
ACTUAL -
Upon pressing the Reset button the textfields (i.e. Roll No, Name, Marks)
values are not reset. Nothing happens to textfield values.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
// 1) Example of event handling within class

import java.awt.*;
import java.awt.event.*;
import java.io.*;
      
class Ideone extends Frame
{
Label lblName, lblRollNo, lblMarks;
TextField txtName, txtRollNo, txtMarks;
Button btnReset, btnSave;

Ideone()
{
setLayout(new GridLayout(4, 2));
setTitle("Student Record Maintainer");
setSize(280,300);
setVisible(true);

lblName = new Label("Name: ");
txtName = new TextField("", 20);

lblRollNo = new Label("Roll No.: ");
txtRollNo = new TextField("", 20);

lblMarks = new Label("Marks: ");
txtMarks = new TextField("", 20);

btnReset = new Button("Reset");
btnSave = new Button("Save");

btnReset.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
txtName.setText("");
txtRollNo.setText("");
txtMarks.setText("");
}
});

btnSave.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent ae){
System.out.println(txtName.getText());
System.out.println(txtRollNo.getText());
System.out.println(txtMarks.getText());
}
});

addWindowListener( new WindowAdapter() {
public void windowClosing(WindowEvent we) {
System.exit(0);
}
}
);

add(lblName); add(txtName);
add(lblRollNo); add(txtRollNo);
add(lblMarks); add(txtMarks);
add(btnReset); add(btnSave);
    }
      
    public static void main(String args[]) throws java.lang.Exception
{
new Ideone();
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
1) before setting the text by setText() method If we call setText() method with non-empty string it works.

2) Before setting the text by setText() method If we call getText() method and then call setText method it also works.