1. Description
2. Method Summary
3. Method Details
   1. length()
   2. charAt(int)
   3. isEmpty()
   4. subSequence(int, int)
   5. toString()
   6. chars()
   7. codePoints()
   8. compare(CharSequence, CharSequence)
   9. getChars(int, int, char[], int)

• Method Summary

  All MethodsStatic MethodsInstance MethodsAbstract MethodsDefault Methods

  Modifier and Type

  Method

  Description

  char

  charAt(int index)

  Returns the char value at the specified index.

  default IntStream

  chars()

  Returns a stream of int zero-extending the char values from this sequence.

  default IntStream

  codePoints()

  Returns a stream of code point values from this sequence.

  static int

  compare(CharSequence cs1, CharSequence cs2)

  Compares two CharSequence instances lexicographically.

  default void

  getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)

  Copies characters from this sequence into the given destination array.

  default boolean

  isEmpty()

  Returns true if this character sequence is empty.

  int

  length()

  Returns the length of this character sequence.

  CharSequence

  subSequence(int start, int end)

  Returns a CharSequence that is a subsequence of this sequence.

  String

  toString()

  Returns a string containing the characters in this sequence in the same order as this sequence.

• Method Details

  • length

    int length()

    Returns the length of this character sequence. The length is the number of 16-bit chars in the sequence.

    Returns: the number of chars in this sequence

  • charAt

    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.

    Parameters: index - the index of the char value to be returned Returns: the specified char value Throws: IndexOutOfBoundsException - if the index argument is negative or not less than length()

  • isEmpty

    default boolean isEmpty()

    Returns true if this character sequence is empty.

    Implementation Requirements: The default implementation returns the result of calling length() == 0. Returns: true if length() is 0, otherwise false Since: 15

  • subSequence

    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.

    Parameters: start - the start index, inclusive end - the end index, exclusive Returns: the specified subsequence Throws: IndexOutOfBoundsException - if start or end are negative, if end is greater than length(), or if start is greater than end

  • toString

    String toString()

    Returns a string containing the characters in this sequence in the same order as this sequence. The length of the string will be the length of this sequence.

    Overrides: toString in class Object Returns: a string consisting of exactly this sequence of characters

  • chars

    default IntStream chars()

    Returns a stream of int zero-extending the char values from this sequence. Any char which maps to a surrogate code point is passed through uninterpreted.

    The stream binds to this sequence when the terminal stream operation commences (specifically, for mutable sequences the spliterator for the stream is late-binding). If the sequence is modified during that operation then the result is undefined.

    Returns: an IntStream of char values from this sequence Since: 1.8

  • codePoints

    default IntStream codePoints()

    Returns a stream of code point values from this sequence. Any surrogate pairs encountered in the sequence are combined as if by Character.toCodePoint and the result is passed to the stream. Any other code units, including ordinary BMP characters, unpaired surrogates, and undefined code units, are zero-extended to int values which are then passed to the stream.

    The stream binds to this sequence when the terminal stream operation commences (specifically, for mutable sequences the spliterator for the stream is late-binding). If the sequence is modified during that operation then the result is undefined.

    Returns: an IntStream of Unicode code points from this sequence Since: 1.8

  • compare

    static int compare(CharSequence cs1, CharSequence cs2)

    Compares two CharSequence instances lexicographically. Returns a negative value, zero, or a positive value if the first sequence is lexicographically less than, equal to, or greater than the second, respectively.

    The lexicographical ordering of CharSequence is defined as follows. Consider a CharSequence cs of length len to be a sequence of char values, cs[0] to cs[len-1]. Suppose k is the lowest index at which the corresponding char values from each sequence differ. The lexicographic ordering of the sequences is determined by a numeric comparison of the char values cs1[k] with cs2[k]. If there is no such index k, the shorter sequence is considered lexicographically less than the other. If the sequences have the same length, the sequences are considered lexicographically equal.

    Parameters: cs1 - the first CharSequence cs2 - the second CharSequence Returns: the value 0 if the two CharSequence are equal; a negative integer if the first CharSequence is lexicographically less than the second; or a positive integer if the first CharSequence is lexicographically greater than the second. Since: 11

  • getChars

    default void getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)

    Copies characters from this sequence into the given destination array. The first character to be copied is at index srcBegin; the last character to be copied is at index srcEnd-1. The total number of characters to be copied is srcEnd-srcBegin. The characters are copied into the subarray of dst starting at index dstBegin and ending at index: dstbegin + (srcEnd-srcBegin) - 1

    Implementation Requirements: The default implementation invokes charAt(int index) in a loop iterating index from srcBegin to srcEnd-1. Concurrent truncation of this character sequence can throw IndexOutOfBoundsException. In this case, some characters, but not all, may be already transferred. Parameters: srcBegin - start copying at this offset. srcEnd - stop copying at this offset. dst - the array to copy the data into. dstBegin - offset into dst. Throws: IndexOutOfBoundsException - if any of the following is true:

    • srcBegin is negative
    • dstBegin is negative
    • the srcBegin argument is greater than the srcEnd argument.
    • srcEnd is greater than this.length().
    • dstBegin+srcEnd-srcBegin is greater than dst.length

    NullPointerException - if dst is null Since: 25

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