Java Module java.desktop Package java.awt.font Class TextHitInfo（JDK11）

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

```
public final class TextHitInfo
extends Object
```
The TextHitInfo class 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 query TextHitInfo instances for an insertion offset, where new text is inserted into the text model. The insertion offset is equal 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. The getOtherHit method constructs 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

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static TextHitInfo`	`afterOffset(int offset)`	Creates a `TextHitInfo` at the specified offset, associated with the character after the offset.
`static TextHitInfo`	`beforeOffset(int offset)`	Creates a `TextHitInfo` at the specified offset, associated with the character before the offset.
`boolean`	`equals(TextHitInfo hitInfo)`	Returns `true` if the specified `TextHitInfo` has the same `charIndex` and `isLeadingEdge` as this `TextHitInfo`.
`boolean`	`equals(Object obj)`	Returns `true` if the specified `Object` is a `TextHitInfo` and equals this `TextHitInfo`.
`int`	`getCharIndex()`	Returns the index of the character hit.
`int`	`getInsertionIndex()`	Returns the insertion index.
`TextHitInfo`	`getOffsetHit(int delta)`	Creates a `TextHitInfo` whose character index is offset by `delta` from the `charIndex` of this `TextHitInfo`.
`TextHitInfo`	`getOtherHit()`	Creates a `TextHitInfo` 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)`	Creates a `TextHitInfo` on the leading edge of the character at the specified `charIndex`.
`String`	`toString()`	Returns a `String` representing the hit for debugging use only.
`static TextHitInfo`	`trailing(int charIndex)`	Creates a hit on the trailing edge of the character at the specified `charIndex`.

Methods declared in 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.
    
    Returns:
    
    the index of the character hit.
  - isLeadingEdge
```
public boolean isLeadingEdge()
```
    Returns true if the leading edge of the character was hit.
    
    Returns:
    
    true if the leading edge of the character was hit; false otherwise.
  - 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.
    
    Returns:
    
    the insertion index.
  - hashCode
```
public int hashCode()
```
    Returns the hash code.
    
    Overrides:
    
    hashCode in class Object
    
    Returns:
    
    the hash code of this TextHitInfo, which is also the charIndex of this TextHitInfo.
    
    See Also:
    
    Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)
  - equals
```
public boolean equals(Object obj)
```
    Returns true if the specified Object is a TextHitInfo and equals this TextHitInfo.
    
    Overrides:
    
    equals in class Object
    
    Parameters:
    
    obj - the Object to test for equality
    
    Returns:
    
    true if the specified Object equals this TextHitInfo; false otherwise.
    
    See Also:
    
    Object.hashCode(), HashMap
  - equals
```
public boolean equals(TextHitInfo hitInfo)
```
    Returns true if the specified TextHitInfo has the same charIndex and isLeadingEdge as this TextHitInfo. This is not the same as having the same insertion offset.
    
    Parameters:
    
    hitInfo - a specified TextHitInfo
    
    Returns:
    
    true if the specified TextHitInfo has the same charIndex and isLeadingEdge as this TextHitInfo.
  - toString
```
public String toString()
```
    Returns a String representing the hit for debugging use only.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    a String representing this TextHitInfo.
  - leading
```
public static TextHitInfo leading(int charIndex)
```
    Creates a TextHitInfo on the leading edge of the character at the specified charIndex.
    
    Parameters:
    
    charIndex - the index of the character hit
    
    Returns:
    
    a TextHitInfo on the leading edge of the character at the specified charIndex.
  - trailing
```
public static TextHitInfo trailing(int charIndex)
```
    Creates a hit on the trailing edge of the character at the specified charIndex.
    
    Parameters:
    
    charIndex - the index of the character hit
    
    Returns:
    
    a TextHitInfo on the trailing edge of the character at the specified charIndex.
  - beforeOffset
```
public static TextHitInfo beforeOffset(int offset)
```
    Creates a TextHitInfo at the specified offset, associated with the character before the offset.
    
    Parameters:
    
    offset - an offset associated with the character before the offset
    
    Returns:
    
    a TextHitInfo at the specified offset.
  - afterOffset
```
public static TextHitInfo afterOffset(int offset)
```
    Creates a TextHitInfo at the specified offset, associated with the character after the offset.
    
    Parameters:
    
    offset - an offset associated with the character after the offset
    
    Returns:
    
    a TextHitInfo at the specified offset.
  - getOtherHit
```
public TextHitInfo getOtherHit()
```
    Creates a TextHitInfo on the other side of the insertion point. This TextHitInfo remains unchanged.
    
    Returns:
    
    a TextHitInfo on the other side of the insertion point.
  - getOffsetHit
```
public TextHitInfo getOffsetHit(int delta)
```
    Creates a TextHitInfo whose character index is offset by delta from the charIndex of this TextHitInfo. This TextHitInfo remains unchanged.
    
    Parameters:
    
    delta - the value to offset this charIndex
    
    Returns:
    
    a TextHitInfo whose charIndex is offset by delta from the charIndex of this TextHitInfo.

Java Module java.desktop Package java.awt.font Class TextHitInfo（JDK11）

Class TextHitInfo

Method Summary

Methods declared in class java.lang.Object

Method Detail

getCharIndex

isLeadingEdge

getInsertionIndex

hashCode

equals

equals

toString

leading

trailing

beforeOffset

afterOffset

getOtherHit

getOffsetHit