class:JPanel [NONE]

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible

Direct Known Subclasses:

AbstractColorChooserPanel, JSpinner.DefaultEditor
```
@JavaBean(defaultProperty="UI",
          description="A generic lightweight container.")
public class JPanel
extends JComponent
implements Accessible
```
JPanel is a generic lightweight container. For examples and task-oriented documentation for JPanel, see How to Use Panels , a section in The Java Tutorial .
Warning: Swing is not thread safe. For more information see Swing's Threading Policy .

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans™ has been added to the java.beans package. Please see XMLEncoder.

Since:

1.2

constructor:JPanel(java.awt.LayoutManager,boolean) [NONE]

JPanel
```
public JPanel(LayoutManager layout,
              boolean isDoubleBuffered)
```
Creates a new JPanel with the specified layout manager and buffering strategy.

Parameters:

layout - the LayoutManager to use

isDoubleBuffered - a boolean, true for double-buffering, which uses additional memory space to achieve fast, flicker-free updates

constructor:JPanel(java.awt.LayoutManager) [NONE]

JPanel
```
public JPanel(LayoutManager layout)
```
Create a new buffered JPanel with the specified layout manager

Parameters:

layout - the LayoutManager to use

constructor:JPanel(boolean) [NONE]

JPanel
```
public JPanel(boolean isDoubleBuffered)
```
Creates a new JPanel with FlowLayout and the specified buffering strategy. If isDoubleBuffered is true, the JPanel will use a double buffer.

Parameters:

isDoubleBuffered - a boolean, true for double-buffering, which uses additional memory space to achieve fast, flicker-free updates

constructor:JPanel() [NONE]

JPanel
```
public JPanel()
```
Creates a new JPanel with a double buffer and a flow layout.

method:updateUI() [NONE]

updateUI
```
public void updateUI()
```
Resets the UI property with a value from the current look and feel.

Overrides:

updateUI in class JComponent

See Also:

JComponent.updateUI()

method:getUI() [NONE]

getUI
```
public PanelUI getUI()
```
Returns the look and feel (L&F) object that renders this component.

Overrides:

getUI in class JComponent

Returns:

the PanelUI object that renders this component

Since:

1.4

method:setUI(javax.swing.plaf.PanelUI) [NONE]

setUI

@BeanProperty(hidden=true,
              visualUpdate=true,
              description="The UI object that implements the Component\'s LookAndFeel.")
public void setUI(PanelUI ui)

Sets the look and feel (L&F) object that renders this component.

Parameters:: ui - the PanelUI L&F object
Since:: 1.4
See Also:: UIDefaults.getUI(javax.swing.JComponent)

method:getUIClassID() [NONE]

getUIClassID
```
@BeanProperty(bound=false,
              expert=true,
              description="A string that specifies the name of the L&F class.")
public String getUIClassID()
```
Returns a string that specifies the name of the L&F class that renders this component.

Overrides:

getUIClassID in class JComponent

Returns:

the string "PanelUI"

See Also:

JComponent.getUIClassID(), UIDefaults.getUI(javax.swing.JComponent)

method:paramString() [NONE]

paramString
```
protected String paramString()
```
Returns a string representation of this JPanel. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null.

Overrides:

paramString in class JComponent

Returns:

a string representation of this JPanel.

method:getAccessibleContext() [NONE]

getAccessibleContext
```
@BeanProperty(bound=false)
public AccessibleContext getAccessibleContext()
```
Gets the AccessibleContext associated with this JPanel. For JPanels, the AccessibleContext takes the form of an AccessibleJPanel. A new AccessibleJPanel instance is created if necessary.

Specified by:

getAccessibleContext in interface Accessible

Overrides:

getAccessibleContext in class Component

Returns:

an AccessibleJPanel that serves as the AccessibleContext of this JPanel