| JavaTM 2 Platform Std. Ed. v1.4.2
java.awt
Class ComponentOrientation
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",
BL means "items bottom-to-top, lines bottom-to-top", 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
| Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
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.
isHorizontal
public boolean isHorizontal()
- Are lines horizontal?
This will return true for horizontal, left-to-right writing
systems such as Roman.
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.
getOrientation
public static ComponentOrientation getOrientation(Locale locale)
- Returns the orientation that is appropriate for the given locale.
- Parameters:
locale - the specified locale
getOrientation
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.
Copyright 2003 Sun Microsystems, Inc. All rights reserved
|
