Java Module java.desktop Package java.awt Class ComponentOrientation（JDK11）

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java.lang.Object
- java.awt.ComponentOrientation

All Implemented Interfaces:

Serializable
```
public final class ComponentOrientation
extends Object
implements Serializable
```
The ComponentOrientation class encapsulates the language-sensitive orientation that is to be used to order the elements of a component or of text. It is used to reflect the differences in this ordering between Western alphabets, Middle Eastern (such as Hebrew), and Far Eastern (such as Japanese).
Fundamentally, this governs items (such as characters) which are laid out in lines, with the lines then laid out in a block. This also applies to items in a widget: for example, in a check box where the box is positioned relative to the text.

There are four different orientations used in modern languages as in the following table.
```
 LT          RT          TL          TR
 A B C       C B A       A D G       G D A
 D E F       F E D       B E H       H E B
 G H I       I H G       C F I       I F C
 
```
(In the header, the two-letter abbreviation represents the item direction in the first letter, and the line direction in the second. For example, LT means "items left-to-right, lines top-to-bottom", TL means "items top-to-bottom, lines left-to-right", and so on.)
The orientations are:
- LT - Western Europe (optional for Japanese, Chinese, Korean)
- RT - Middle East (Arabic, Hebrew)
- TR - Japanese, Chinese, Korean
- TL - Mongolian
Components whose view and controller code depends on orientation should use the isLeftToRight() and isHorizontal() methods to determine their behavior. They should not include switch-like code that keys off of the constants, such as:
```
 if (orientation == LEFT_TO_RIGHT) {
   ...
 } else if (orientation == RIGHT_TO_LEFT) {
   ...
 } else {
   // Oops
 }
 
```
This is unsafe, since more constants may be added in the future and since it is not guaranteed that orientation objects will be unique.
See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field	Description
`static ComponentOrientation`	`LEFT_TO_RIGHT`	Items run left to right and lines flow top to bottom Examples: English, French.
`static ComponentOrientation`	`RIGHT_TO_LEFT`	Items run right to left and lines flow top to bottom Examples: Arabic, Hebrew.
`static ComponentOrientation`	`UNKNOWN`	Indicates that a component's orientation has not been set.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`static ComponentOrientation`	`getOrientation(Locale locale)`	Returns the orientation that is appropriate for the given locale.
`static ComponentOrientation`	`getOrientation(ResourceBundle bdl)`	Deprecated. As of J2SE 1.4, use `getOrientation(java.util.Locale)`.
`boolean`	`isHorizontal()`	Are lines horizontal?
`boolean`	`isLeftToRight()`	HorizontalLines: Do items run left-to-right?

Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - LEFT_TO_RIGHT
```
public static final ComponentOrientation LEFT_TO_RIGHT
```
    Items run left to right and lines flow top to bottom Examples: English, French.
  - RIGHT_TO_LEFT
```
public static final ComponentOrientation RIGHT_TO_LEFT
```
    Items run right to left and lines flow top to bottom Examples: Arabic, Hebrew.
  - UNKNOWN
```
public static final ComponentOrientation UNKNOWN
```
    Indicates that a component's orientation has not been set. To preserve the behavior of existing applications, isLeftToRight will return true for this value.
- Method Detail
  - isHorizontal
```
public boolean isHorizontal()
```
    Are lines horizontal? This will return true for horizontal, left-to-right writing systems such as Roman.
    
    Returns:
    
    true if this orientation has horizontal lines
  - isLeftToRight
```
public boolean isLeftToRight()
```
    HorizontalLines: Do items run left-to-right?
    Vertical Lines: Do lines run left-to-right?
    This will return true for horizontal, left-to-right writing systems such as Roman.
    
    Returns:
    
    true if this orientation is left-to-right
  - getOrientation
```
public static ComponentOrientation getOrientation(Locale locale)
```
    Returns the orientation that is appropriate for the given locale.
    
    Parameters:
    
    locale - the specified locale
    
    Returns:
    
    the orientation for the locale
  - getOrientation
```
@Deprecated
public static ComponentOrientation getOrientation(ResourceBundle bdl)
```
    Deprecated.
    As of J2SE 1.4, use getOrientation(java.util.Locale).
    Returns the orientation appropriate for the given ResourceBundle's localization. Three approaches are tried, in the following order:
    
    Retrieve a ComponentOrientation object from the ResourceBundle using the string "Orientation" as the key.
    
    Use the ResourceBundle.getLocale to determine the bundle's locale, then return the orientation for that locale.
    
    Return the default locale's orientation.
    Parameters:
    
    bdl - the bundle to use
    
    Returns:
    
    the orientation

Java Module java.desktop Package java.awt Class ComponentOrientation（JDK11）

Class ComponentOrientation

Field Summary

Method Summary

Methods declared in class java.lang.Object

Field Detail

LEFT_TO_RIGHT

RIGHT_TO_LEFT

UNKNOWN

Method Detail

isHorizontal

isLeftToRight

getOrientation

getOrientation