Java javax.swing.text Class Segment（JDK8）

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Java™ Platform
Standard Ed. 8

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java.lang.Object
- javax.swing.text.Segment

All Implemented Interfaces:

CharSequence, Cloneable, CharacterIterator
```
public class Segment
extends Object
implements Cloneable, CharacterIterator, CharSequence
```
A segment of a character array representing a fragment of text. It should be treated as immutable even though the array is directly accessible. This gives fast access to fragments of text without the overhead of copying around characters. This is effectively an unprotected String.
The Segment implements the java.text.CharacterIterator interface to support use with the i18n support without copying text into a string.

Field Summary

Fields
Modifier and Type	Field and Description
`char[]`	`array` This is the array containing the text of interest.
`int`	`count` This is the number of array elements that make up the text of interest.
`int`	`offset` This is the offset into the array that the desired text begins.

Fields inherited from interface java.text.CharacterIterator
DONE

Constructor Summary

Constructors
Constructor and Description
`Segment()` Creates a new segment.
`Segment(char[] array, int offset, int count)` Creates a new segment referring to an existing array.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`char`	`charAt(int index)` Returns the `char` value at the specified index.
`Object`	`clone()` Creates a shallow copy.
`char`	`current()` Gets the character at the current position (as returned by getIndex()).
`char`	`first()` Sets the position to getBeginIndex() and returns the character at that position.
`int`	`getBeginIndex()` Returns the start index of the text.
`int`	`getEndIndex()` Returns the end index of the text.
`int`	`getIndex()` Returns the current index.
`boolean`	`isPartialReturn()` Flag to indicate that partial returns are valid.
`char`	`last()` Sets the position to getEndIndex()-1 (getEndIndex() if the text is empty) and returns the character at that position.
`int`	`length()` Returns the length of this character sequence.
`char`	`next()` Increments the iterator's index by one and returns the character at the new index.
`char`	`previous()` Decrements the iterator's index by one and returns the character at the new index.
`char`	`setIndex(int position)` Sets the position to the specified position in the text and returns that character.
`void`	`setPartialReturn(boolean p)` Flag to indicate that partial returns are valid.
`CharSequence`	`subSequence(int start, int end)` Returns a `CharSequence` that is a subsequence of this sequence.
`String`	`toString()` Converts a segment into a String.

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

Methods inherited from interface java.lang.CharSequence
chars, codePoints

- Field Detail
  - array
```
public char[] array
```
    This is the array containing the text of interest. This array should never be modified; it is available only for efficiency.
  - offset
```
public int offset
```
    This is the offset into the array that the desired text begins.
  - count
```
public int count
```
    This is the number of array elements that make up the text of interest.
- Constructor Detail
  - Segment
```
public Segment()
```
    Creates a new segment.
  - Segment
```
public Segment(char[] array,
               int offset,
               int count)
```
    Creates a new segment referring to an existing array.
    
    Parameters:
    
    array - the array to refer to
    
    offset - the offset into the array
    
    count - the number of characters
- Method Detail
  - setPartialReturn
```
public void setPartialReturn(boolean p)
```
    Flag to indicate that partial returns are valid. If the flag is true, an implementation of the interface method Document.getText(position,length,Segment) should return as much text as possible without making a copy. The default state of the flag is false which will cause Document.getText(position,length,Segment) to provide the same return behavior it always had, which may or may not make a copy of the text depending upon the request.
    
    Parameters:
    
    p - whether or not partial returns are valid.
    
    Since:
    
    1.4
  - isPartialReturn
```
public boolean isPartialReturn()
```
    Flag to indicate that partial returns are valid.
    
    Returns:
    
    whether or not partial returns are valid.
    
    Since:
    
    1.4
  - toString
```
public String toString()
```
    Converts a segment into a String.
    
    Specified by:
    
    toString in interface CharSequence
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    the string
  - first
```
public char first()
```
    Sets the position to getBeginIndex() and returns the character at that position.
    
    Specified by:
    
    first in interface CharacterIterator
    
    Returns:
    
    the first character in the text, or DONE if the text is empty
    
    Since:
    
    1.3
    
    See Also:
    
    getBeginIndex()
  - last
```
public char last()
```
    Sets the position to getEndIndex()-1 (getEndIndex() if the text is empty) and returns the character at that position.
    
    Specified by:
    
    last in interface CharacterIterator
    
    Returns:
    
    the last character in the text, or DONE if the text is empty
    
    Since:
    
    1.3
    
    See Also:
    
    getEndIndex()
  - current
```
public char current()
```
    Gets the character at the current position (as returned by getIndex()).
    
    Specified by:
    
    current in interface CharacterIterator
    
    Returns:
    
    the character at the current position or DONE if the current position is off the end of the text.
    
    Since:
    
    1.3
    
    See Also:
    
    getIndex()
  - next
```
public char next()
```
    Increments the iterator's index by one and returns the character at the new index. If the resulting index is greater or equal to getEndIndex(), the current index is reset to getEndIndex() and a value of DONE is returned.
    
    Specified by:
    
    next in interface CharacterIterator
    
    Returns:
    
    the character at the new position or DONE if the new position is off the end of the text range.
    
    Since:
    
    1.3
  - previous
```
public char previous()
```
    Decrements the iterator's index by one and returns the character at the new index. If the current index is getBeginIndex(), the index remains at getBeginIndex() and a value of DONE is returned.
    
    Specified by:
    
    previous in interface CharacterIterator
    
    Returns:
    
    the character at the new position or DONE if the current position is equal to getBeginIndex().
    
    Since:
    
    1.3
  - setIndex
```
public char setIndex(int position)
```
    Sets the position to the specified position in the text and returns that character.
    
    Specified by:
    
    setIndex in interface CharacterIterator
    
    Parameters:
    
    position - the position within the text. Valid values range from getBeginIndex() to getEndIndex(). An IllegalArgumentException is thrown if an invalid value is supplied.
    
    Returns:
    
    the character at the specified position or DONE if the specified position is equal to getEndIndex()
    
    Since:
    
    1.3
  - getBeginIndex
```
public int getBeginIndex()
```
    Returns the start index of the text.
    
    Specified by:
    
    getBeginIndex in interface CharacterIterator
    
    Returns:
    
    the index at which the text begins.
    
    Since:
    
    1.3
  - getEndIndex
```
public int getEndIndex()
```
    Returns the end index of the text. This index is the index of the first character following the end of the text.
    
    Specified by:
    
    getEndIndex in interface CharacterIterator
    
    Returns:
    
    the index after the last character in the text
    
    Since:
    
    1.3
  - getIndex
```
public int getIndex()
```
    Returns the current index.
    
    Specified by:
    
    getIndex in interface CharacterIterator
    
    Returns:
    
    the current index.
    
    Since:
    
    1.3
  - charAt
```
public char charAt(int index)
```
    Returns the char value at the specified index. An index ranges from zero to length() - 1. The first char value of the sequence is at index zero, the next at index one, and so on, as for array indexing.
    If the char value specified by the index is a surrogate, the surrogate value is returned.
    
    Specified by:
    
    charAt in interface CharSequence
    
    Parameters:
    
    index - the index of the char value to be returned
    
    Returns:
    
    the specified char value
    
    Since:
    
    1.6
  - length
```
public int length()
```
    Returns the length of this character sequence. The length is the number of 16-bit chars in the sequence.
    
    Specified by:
    
    length in interface CharSequence
    
    Returns:
    
    the number of chars in this sequence
    
    Since:
    
    1.6
  - subSequence
```
public CharSequence subSequence(int start,
                                int end)
```
    Returns a CharSequence that is a subsequence of this sequence. The subsequence starts with the char value at the specified index and ends with the char value at index end - 1. The length (in chars) of the returned sequence is end - start, so if start == end then an empty sequence is returned.
    
    Specified by:
    
    subSequence in interface CharSequence
    
    Parameters:
    
    start - the start index, inclusive
    
    end - the end index, exclusive
    
    Returns:
    
    the specified subsequence
    
    Since:
    
    1.6
  - clone
```
public Object clone()
```
    Creates a shallow copy.
    
    Specified by:
    
    clone in interface CharacterIterator
    
    Overrides:
    
    clone in class Object
    
    Returns:
    
    the copy
    
    See Also:
    
    Cloneable

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Java™ Platform
Standard Ed. 8

All Classes

Summary:
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Field |
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Method

Detail:
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For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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Java javax.swing.text Class Segment（JDK8）

Class Segment

Field Summary

Fields inherited from interface java.text.CharacterIterator

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.lang.CharSequence

Field Detail

array

offset

count

Constructor Detail

Segment

Segment

Method Detail

setPartialReturn

isPartialReturn

toString

first

last

current

next

previous

setIndex

getBeginIndex

getEndIndex

getIndex

charAt

length

subSequence

clone