Module java.base
Package java.text

Class FieldPosition

java.lang.Object
java.text.FieldPosition
public class FieldPosition
extends Object
FieldPosition is a simple class used by Format and its subclasses to identify fields in formatted output. Fields can be identified in two ways:
  • By an integer constant, whose names typically end with _FIELD. The constants are defined in the various subclasses of Format.
  • By a Format.Field constant, see ERA_FIELD and its friends in DateFormat for an example.

FieldPosition keeps track of the position of the field within the formatted output with two indices: the index of the first character of the field and the index of the last character of the field.

One version of the format method in the various Format classes requires a FieldPosition object as an argument. You use this format method to perform partial formatting or to get information about the formatted output (such as the position of a field).

If you are interested in the positions of all attributes in the formatted string use the Format method formatToCharacterIterator.

Since:
1.1
See Also:
Format

  • Constructor Summary

    Constructors 
    Constructor Description
    FieldPosition​(int field)
    Creates a FieldPosition object for the given field.
    FieldPosition​(Format.Field attribute)
    Creates a FieldPosition object for the given field constant.
    FieldPosition​(Format.Field attribute, int fieldID)
    Creates a FieldPosition object for the given field.

  • Method Summary

    Modifier and Type Method Description
    boolean equals​(Object obj)
    Overrides equals
    int getBeginIndex()
    Retrieves the index of the first character in the requested field.
    int getEndIndex()
    Retrieves the index of the character following the last character in the requested field.
    int getField()
    Retrieves the field identifier.
    Format.Field getFieldAttribute()
    Returns the field identifier as an attribute constant from one of the Field subclasses.
    int hashCode()
    Returns a hash code for this FieldPosition.
    void setBeginIndex​(int bi)
    Sets the begin index.
    void setEndIndex​(int ei)
    Sets the end index.
    String toString()
    Return a string representation of this FieldPosition.

    Methods declared in class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Constructor Details

    • FieldPosition

      public FieldPosition​(int field)
      Creates a FieldPosition object for the given field. Fields are identified by constants, whose names typically end with _FIELD, in the various subclasses of Format.
      Parameters:
      field - the field identifier
      See Also:
      NumberFormat.INTEGER_FIELD, NumberFormat.FRACTION_FIELD, DateFormat.YEAR_FIELD, DateFormat.MONTH_FIELD

    • FieldPosition

      public FieldPosition​(Format.Field attribute)
      Creates a FieldPosition object for the given field constant. Fields are identified by constants defined in the various Format subclasses. This is equivalent to calling new FieldPosition(attribute, -1).
      Parameters:
      attribute - Format.Field constant identifying a field
      Since:
      1.4

    • FieldPosition

      public FieldPosition​(Format.Field attribute, int fieldID)
      Creates a FieldPosition object for the given field. The field is identified by an attribute constant from one of the Field subclasses as well as an integer field ID defined by the Format subclasses. Format subclasses that are aware of Field should give precedence to attribute and ignore fieldID if attribute is not null. However, older Format subclasses may not be aware of Field and rely on fieldID. If the field has no corresponding integer constant, fieldID should be -1.
      Parameters:
      attribute - Format.Field constant identifying a field
      fieldID - integer constant identifying a field
      Since:
      1.4

  • Method Details

    • getFieldAttribute

      public Format.Field getFieldAttribute()
      Returns the field identifier as an attribute constant from one of the Field subclasses. May return null if the field is specified only by an integer field ID.
      Returns:
      Identifier for the field
      Since:
      1.4

    • getField

      public int getField()
      Retrieves the field identifier.
      Returns:
      the field identifier

    • getBeginIndex

      public int getBeginIndex()
      Retrieves the index of the first character in the requested field.
      Returns:
      the begin index

    • getEndIndex

      public int getEndIndex()
      Retrieves the index of the character following the last character in the requested field.
      Returns:
      the end index

    • setBeginIndex

      public void setBeginIndex​(int bi)
      Sets the begin index. For use by subclasses of Format.
      Parameters:
      bi - the begin index
      Since:
      1.2

    • setEndIndex

      public void setEndIndex​(int ei)
      Sets the end index. For use by subclasses of Format.
      Parameters:
      ei - the end index
      Since:
      1.2

    • equals

      public boolean equals​(Object obj)
      Overrides equals
      Overrides:
      equals in class Object
      Parameters:
      obj - the reference object with which to compare.
      Returns:
      true if this object is the same as the obj argument; false otherwise.
      See Also:
      Object.hashCode(), HashMap

    • hashCode

      public int hashCode()
      Returns a hash code for this FieldPosition.
      Overrides:
      hashCode in class Object
      Returns:
      a hash code value for this object
      See Also:
      Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

    • toString

      public String toString()
      Return a string representation of this FieldPosition.
      Overrides:
      toString in class Object
      Returns:
      a string representation of this object