Class java.awt.font.TextHitInfo

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Java Platform 1.2
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Class java.awt.font.TextHitInfo

java.lang.Object
  |
  +--java.awt.font.TextHitInfo

public final class TextHitInfo
extends Object

TextHitInfo represents a character position in a text model, and a bias, or "side," of the character. Biases are either leading (the left edge, for a left-to-right character) or trailing (the right edge, for a left-to-right character). Instances of TextHitInfo are used to specify caret and insertion positions within text.

For example, consider the text "abc". TextHitInfo.trailing(1) corresponds to the right side of the 'b' in the text.

TextHitInfo is used primarily by TextLayout and clients of TextLayout. Clients of TextLayout will query TextHitInfo instances for an insertion offset, where new text will be inserted into the text model. The insertion offset is equals to the character position in the TextHitInfo if the bias is leading, and one character after if the bias is trailing. The insertion offset for TextHitInfo.trailing(1) is 2.

Sometimes it is convenient to construct a TextHitInfo with the same insertion offset as an existing one, but on the opposite character. getOtherHit will construct a new TextHitInfo with the same insertion offset as an existing one, with a hit on the character on the other side of the insertion offset. Calling getOtherHit on trailing(1) would return leading(2). In general, getOtherHit for trailing(n) returns leading(n+1) and getOtherHit for leading(n) returns trailing(n-1).

Example:

Converting a graphical point to an insertion point within a text model

 TextLayout layout = ...;
 Point2D.Float hitPoint = ...;
 TextHitInfo hitInfo = layout.hitTestChar(hitPoint.x, hitPoint.y);
 int insPoint = hitInfo.getInsertionIndex();
 // insPoint is relative to layout;  may need to adjust for use 
 // in a text model

See Also:: TextLayout

Method Summary
static TextHitInfo	afterOffset(int offset) Create a hit at offset, associated with the character after the offset.
static TextHitInfo	beforeOffset(int offset) Create a hit at offset, associated with the character before the offset.
boolean	equals(Object obj) Return true if the object is a TextHitInfo and this TextHitInfo is equal to it.
boolean	equals(TextHitInfo hitInfo) Return true if the hit's character index and edge are the same.
int	getCharIndex() Returns the index of the character hit.
int	getInsertionIndex() Returns the insertion index.
TextHitInfo	getOffsetHit(int delta) Creates a hit whose character index is offset by delta from this hit.
TextHitInfo	getOtherHit() Creates a hit on the other side of the insertion point.
int	hashCode() Returns the hash code.
boolean	isLeadingEdge() Returns true if the leading edge of the character was hit.
static TextHitInfo	leading(int charIndex) Create a hit on the leading edge of the character at charIndex.
String	toString() Return a string representing the hit, for debugging use only.
static TextHitInfo	trailing(int charIndex) Create a hit on the trailing edge of the character at charIndex.

Methods inherited from class java.lang.Object
clone , finalize , getClass , notify , notifyAll , wait , wait , wait

Method Detail

getCharIndex

public int getCharIndex()

Returns the index of the character hit.

isLeadingEdge

public boolean isLeadingEdge()

Returns true if the leading edge of the character was hit.

getInsertionIndex

public int getInsertionIndex()

Returns the insertion index. This is the character index if the leading edge of the character was hit, and one greater than the character index if the trailing edge was hit.

hashCode

public int hashCode()

Returns the hash code.

Overrides:: hashCode in class Object

equals

public boolean equals(Object obj)

Return true if the object is a TextHitInfo and this TextHitInfo is equal to it.

Overrides:: equals in class Object

equals

public boolean equals(TextHitInfo hitInfo)

Return true if the hit's character index and edge are the same. This is not the same as having the same insertion offset.

toString

public String toString()

Return a string representing the hit, for debugging use only.

Overrides:: toString in class Object

leading

public static TextHitInfo leading(int charIndex)

Create a hit on the leading edge of the character at charIndex.

trailing

public static TextHitInfo trailing(int charIndex)

Create a hit on the trailing edge of the character at charIndex.

beforeOffset

public static TextHitInfo beforeOffset(int offset)

Create a hit at offset, associated with the character before the offset.

afterOffset

public static TextHitInfo afterOffset(int offset)

Create a hit at offset, associated with the character after the offset.

getOtherHit

public TextHitInfo getOtherHit()

Creates a hit on the other side of the insertion point. This hit remains unchanged.

getOffsetHit

public TextHitInfo getOffsetHit(int delta)

Creates a hit whose character index is offset by delta from this hit. This hit remains unchanged.