Module java.desktop
Package java.awt.font

Class TextHitInfo

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

    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 Details

    • 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.