StringBuilder (GNU libgcj 4.8.0 Documentation)

java.lang.Object
- java.lang.StringBuilder

All Implemented Interfaces:

Serializable, Appendable, CharSequence
```
public final class StringBuilder
extends Object
implements Serializable, CharSequence, Appendable
```
StringBuilder represents a changeable String. It provides the operations required to modify the StringBuilder, including insert, replace, delete, append, and reverse. It like StringBuffer, but is not synchronized. It is ideal for use when it is known that the object will only be used from a single thread.
StringBuilders are variable-length in nature, so even if you initialize them to a certain size, they can still grow larger than that. Capacity indicates the number of characters the StringBuilder can have in it before it has to grow (growing the char array is an expensive operation involving new).
Incidentally, compilers often implement the String operator "+" by using a StringBuilder operation:
a + b
is the same as
new StringBuilder().append(a).append(b).toString().
Classpath's StringBuilder is capable of sharing memory with Strings for efficiency. This will help when a StringBuilder is converted to a String and the StringBuilder is not changed after that (quite common when performing string concatenation).

Since:

1.5

See Also:
String, StringBuffer, Serialized Form

Constructor Summary

Constructors
Constructor and Description
`StringBuilder()` Create a new StringBuilder with default capacity 16.
`StringBuilder(CharSequence seq)` Create a new `StringBuilder` with the characters in the specified `CharSequence`.
`StringBuilder(int capacity)` Create an empty `StringBuilder` with the specified initial capacity.
`StringBuilder(String str)` Create a new `StringBuilder` with the characters in the specified `String`.

Method Summary

Methods
Modifier and Type	Method and Description
`StringBuilder`	`append(boolean bool)` Append the `String` value of the argument to this `StringBuilder`.
`StringBuilder`	`append(char ch)` Append the `char` to this `StringBuilder`.
`StringBuilder`	`append(char[] data)` Append the `char` array to this `StringBuilder`.
`StringBuilder`	`append(char[] data, int offset, int count)` Append part of the `char` array to this `StringBuilder`.
`StringBuilder`	`append(CharSequence seq)` Append the characters in the `CharSequence` to this buffer.
`StringBuilder`	`append(CharSequence seq, int start, int end)` Append some characters from the `CharSequence` to this buffer.
`StringBuilder`	`append(double dnum)` Append the `String` value of the argument to this `StringBuilder`.
`StringBuilder`	`append(float fnum)` Append the `String` value of the argument to this `StringBuilder`.
`StringBuilder`	`append(int inum)` Append the `String` value of the argument to this `StringBuilder`.
`StringBuilder`	`append(long lnum)` Append the `String` value of the argument to this `StringBuilder`.
`StringBuilder`	`append(Object obj)` Append the `String` value of the argument to this `StringBuilder`.
`StringBuilder`	`append(String str)` Append the `String` to this `StringBuilder`.
`StringBuilder`	`append(StringBuffer stringBuffer)` Append the `StringBuilder` value of the argument to this `StringBuilder`.
`StringBuilder`	`appendCodePoint(int code)` Append the code point to this `StringBuilder`.
`int`	`capacity()` Get the total number of characters this `StringBuilder` can support before it must be grown.
`char`	`charAt(int index)` Get the character at the specified index.
`int`	`codePointAt(int index)` Get the code point at the specified index.
`int`	`codePointBefore(int index)` Get the code point before the specified index.
`int`	`codePointCount(int start, int end)` Return the number of code points between two indices in the `StringBuffer`.
`StringBuilder`	`delete(int start, int end)` Delete characters from this `StringBuilder`.
`StringBuilder`	`deleteCharAt(int index)` Delete a character from this `StringBuilder`.
`void`	`ensureCapacity(int minimumCapacity)` Increase the capacity of this `StringBuffer`.
`void`	`getChars(int srcOffset, int srcEnd, char[] dst, int dstOffset)` Get the specified array of characters.
`int`	`indexOf(String str)` Finds the first instance of a substring in this StringBuilder.
`int`	`indexOf(String str, int fromIndex)` Finds the first instance of a String in this StringBuffer, starting at a given index.
`StringBuilder`	`insert(int offset, boolean bool)` Insert the `String` value of the argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, char ch)` Insert the `char` argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, char[] data)` Insert the `char[]` argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, char[] str, int str_offset, int len)` Insert a subarray of the `char[]` argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, CharSequence sequence)` Insert the `CharSequence` argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, CharSequence sequence, int start, int end)` Insert a subsequence of the `CharSequence` argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, double dnum)` Insert the `String` value of the argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, float fnum)` Insert the `String` value of the argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, int inum)` Insert the `String` value of the argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, long lnum)` Insert the `String` value of the argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, Object obj)` Insert the `String` value of the argument into this `StringBuilder`.
`StringBuilder`	`insert(int offset, String str)` Insert the `String` argument into this `StringBuilder`.
`int`	`lastIndexOf(String str)` Finds the last instance of a substring in this StringBuffer.
`int`	`lastIndexOf(String str, int fromIndex)` Finds the last instance of a String in this StringBuffer, starting at a given index.
`int`	`length()` Get the length of the `String` this `StringBuilder` would create.
`int`	`offsetByCodePoints(int start, int codePoints)` Starting at the given index, this counts forward by the indicated number of code points, and then returns the resulting index.
`StringBuilder`	`replace(int start, int end, String str)` Replace characters between index `start` (inclusive) and `end` (exclusive) with `str`.
`StringBuilder`	`reverse()` Reverse the characters in this StringBuilder.
`void`	`setCharAt(int index, char ch)` Set the character at the specified index.
`void`	`setLength(int newLength)` Set the length of this StringBuffer.
`CharSequence`	`subSequence(int beginIndex, int endIndex)` Creates a substring of this StringBuilder, starting at a specified index and ending at one character before a specified index.
`String`	`substring(int beginIndex)` Creates a substring of this StringBuilder, starting at a specified index and ending at the end of this StringBuilder.
`String`	`substring(int beginIndex, int endIndex)` Creates a substring of this StringBuilder, starting at a specified index and ending at one character before a specified index.
`String`	`toString()` Convert this `StringBuilder` to a `String`.
`void`	`trimToSize()` This may reduce the amount of memory used by the StringBuffer, by resizing the internal array to remove unused space.

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

Methods inherited from interface java.lang.CharSequence
charAt

- Constructor Detail
  - StringBuilder
```
public StringBuilder()
```
    Create a new StringBuilder with default capacity 16.
  - StringBuilder
```
public StringBuilder(int capacity)
```
    Create an empty StringBuilder with the specified initial capacity.
    
    Parameters:
    capacity - the initial capacity
    
    Throws:
    
    NegativeArraySizeException - if capacity is negative
  - StringBuilder
```
public StringBuilder(String str)
```
    Create a new StringBuilder with the characters in the specified String. Initial capacity will be the size of the String plus 16.
    
    Parameters:
    str - the String to convert
    
    Throws:
    
    NullPointerException - if str is null
  - StringBuilder
```
public StringBuilder(CharSequence seq)
```
    Create a new StringBuilder with the characters in the specified CharSequence. Initial capacity will be the length of the sequence plus 16; if the sequence reports a length less than or equal to 0, then the initial capacity will be 16.
    
    Parameters:
    seq - the initializing CharSequence
    
    Throws:
    
    NullPointerException - if str is null
- Method Detail
  - length
```
public int length()
```
    Get the length of the String this StringBuilder would create. Not to be confused with the capacity of the StringBuilder.
    
    Specified by:
    
    length in interface CharSequence
    
    Returns:
    the length of this StringBuilder
    See Also:
    capacity(), setLength(int)
  - capacity
```
public int capacity()
```
    Get the total number of characters this StringBuilder can support before it must be grown. Not to be confused with length.
    
    Returns:
    the capacity of this StringBuilder
    See Also:
    length(), ensureCapacity(int)
  - append
```
public StringBuilder append(Object obj)
```
    Append the String value of the argument to this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    obj - the Object to convert and append
    
    Returns:
    this StringBuilder
    See Also:
    String.valueOf(Object), append(String)
  - append
```
public StringBuilder append(String str)
```
    Append the String to this StringBuilder. If str is null, the String "null" is appended.
    
    Parameters:
    str - the String to append
    
    Returns:
    this StringBuilder
  - append
```
public StringBuilder append(StringBuffer stringBuffer)
```
    Append the StringBuilder value of the argument to this StringBuilder. This behaves the same as append((Object) stringBuffer), except it is more efficient.
    
    Parameters:
    stringBuffer - the StringBuilder to convert and append
    
    Returns:
    this StringBuilder
    See Also:
    append(Object)
  - append
```
public StringBuilder append(char[] data)
```
    Append the char array to this StringBuilder. This is similar (but more efficient) than append(new String(data)), except in the case of null.
    
    Parameters:
    data - the char[] to append
    
    Returns:
    this StringBuilder
    
    Throws:
    
    NullPointerException - if str is null
    See Also:
    append(char[], int, int)
  - append
```
public StringBuilder append(char[] data,
                   int offset,
                   int count)
```
    Append part of the char array to this StringBuilder. This is similar (but more efficient) than append(new String(data, offset, count)), except in the case of null.
    
    Parameters:
    data - the char[] to append
    offset - the start location in str
    count - the number of characters to get from str
    
    Returns:
    this StringBuilder
    
    Throws:
    
    NullPointerException - if str is null
    
    IndexOutOfBoundsException - if offset or count is out of range (while unspecified, this is a StringIndexOutOfBoundsException)
  - append
```
public StringBuilder append(boolean bool)
```
    Append the String value of the argument to this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    bool - the boolean to convert and append
    
    Returns:
    this StringBuilder
    See Also:
    String.valueOf(boolean)
  - append
```
public StringBuilder append(char ch)
```
    Append the char to this StringBuilder.
    
    Specified by:
    
    append in interface Appendable
    
    Parameters:
    ch - the char to append
    
    Returns:
    this StringBuilder
  - append
```
public StringBuilder append(CharSequence seq)
```
    Append the characters in the CharSequence to this buffer.
    
    Specified by:
    
    append in interface Appendable
    
    Parameters:
    seq - the CharSequence providing the characters
    
    Returns:
    this StringBuilder
  - append
```
public StringBuilder append(CharSequence seq,
                   int start,
                   int end)
```
    Append some characters from the CharSequence to this buffer. If the argument is null, the four characters "null" are appended.
    
    Specified by:
    
    append in interface Appendable
    
    Parameters:
    seq - the CharSequence providing the characters
    start - the starting index
    end - one past the final index
    
    Returns:
    this StringBuilder
  - append
```
public StringBuilder append(int inum)
```
    Append the String value of the argument to this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    inum - the int to convert and append
    
    Returns:
    this StringBuilder
    See Also:
    String.valueOf(int)
  - append
```
public StringBuilder append(long lnum)
```
    Append the String value of the argument to this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    lnum - the long to convert and append
    
    Returns:
    this StringBuilder
    See Also:
    String.valueOf(long)
  - append
```
public StringBuilder append(float fnum)
```
    Append the String value of the argument to this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    fnum - the float to convert and append
    
    Returns:
    this StringBuilder
    See Also:
    String.valueOf(float)
  - append
```
public StringBuilder append(double dnum)
```
    Append the String value of the argument to this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    dnum - the double to convert and append
    
    Returns:
    this StringBuilder
    See Also:
    String.valueOf(double)
  - appendCodePoint
```
public StringBuilder appendCodePoint(int code)
```
    Append the code point to this StringBuilder. This is like #append(char), but will append two characters if a supplementary code point is given.
    
    Parameters:
    code - the code point to append
    
    Returns:
    this StringBuilder
    Since:
    
    1.5
    
    See Also:
    Character.toChars(int, char[], int)
  - delete
```
public StringBuilder delete(int start,
                   int end)
```
    Delete characters from this StringBuilder. delete(10, 12) will delete 10 and 11, but not 12. It is harmless for end to be larger than length().
    
    Parameters:
    start - the first character to delete
    end - the index after the last character to delete
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if start or end are out of bounds
  - deleteCharAt
```
public StringBuilder deleteCharAt(int index)
```
    Delete a character from this StringBuilder.
    
    Parameters:
    index - the index of the character to delete
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if index is out of bounds
  - replace
```
public StringBuilder replace(int start,
                    int end,
                    String str)
```
    Replace characters between index start (inclusive) and end (exclusive) with str. If end is larger than the size of this StringBuilder, all characters after start are replaced.
    
    Parameters:
    start - the beginning index of characters to delete (inclusive)
    end - the ending index of characters to delete (exclusive)
    str - the new String to insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if start or end are out of bounds
    
    NullPointerException - if str is null
  - substring
```
public String substring(int beginIndex)
```
    Creates a substring of this StringBuilder, starting at a specified index and ending at the end of this StringBuilder.
    
    Parameters:
    beginIndex - index to start substring (base 0)
    
    Returns:
    new String which is a substring of this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if beginIndex is out of bounds
    See Also:
    substring(int, int)
  - subSequence
```
public CharSequence subSequence(int beginIndex,
                       int endIndex)
```
    Creates a substring of this StringBuilder, starting at a specified index and ending at one character before a specified index. This is implemented the same as substring(beginIndex, endIndex), to satisfy the CharSequence interface.
    
    Specified by:
    
    subSequence in interface CharSequence
    
    Parameters:
    beginIndex - index to start at (inclusive, base 0)
    endIndex - index to end at (exclusive)
    
    Returns:
    new String which is a substring of this StringBuilder
    
    Throws:
    
    IndexOutOfBoundsException - if beginIndex or endIndex is out of bounds
    See Also:
    substring(int, int)
  - substring
```
public String substring(int beginIndex,
               int endIndex)
```
    Creates a substring of this StringBuilder, starting at a specified index and ending at one character before a specified index.
    
    Parameters:
    beginIndex - index to start at (inclusive, base 0)
    endIndex - index to end at (exclusive)
    
    Returns:
    new String which is a substring of this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if beginIndex or endIndex is out of bounds
  - insert
```
public StringBuilder insert(int offset,
                   char[] str,
                   int str_offset,
                   int len)
```
    Insert a subarray of the char[] argument into this StringBuilder.
    
    Parameters:
    offset - the place to insert in this buffer
    str - the char[] to insert
    str_offset - the index in str to start inserting from
    len - the number of characters to insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    NullPointerException - if str is null
    
    StringIndexOutOfBoundsException - if any index is out of bounds
  - insert
```
public StringBuilder insert(int offset,
                   Object obj)
```
    Insert the String value of the argument into this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    offset - the place to insert in this buffer
    obj - the Object to convert and insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    See Also:
    String.valueOf(Object)
  - insert
```
public StringBuilder insert(int offset,
                   String str)
```
    Insert the String argument into this StringBuilder. If str is null, the String "null" is used instead.
    
    Parameters:
    offset - the place to insert in this buffer
    str - the String to insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
  - insert
```
public StringBuilder insert(int offset,
                   CharSequence sequence)
```
    Insert the CharSequence argument into this StringBuilder. If the sequence is null, the String "null" is used instead.
    
    Parameters:
    offset - the place to insert in this buffer
    sequence - the CharSequence to insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    IndexOutOfBoundsException - if offset is out of bounds
  - insert
```
public StringBuilder insert(int offset,
                   CharSequence sequence,
                   int start,
                   int end)
```
    Insert a subsequence of the CharSequence argument into this StringBuilder. If the sequence is null, the String "null" is used instead.
    
    Parameters:
    offset - the place to insert in this buffer
    sequence - the CharSequence to insert
    start - the starting index of the subsequence
    end - one past the ending index of the subsequence
    
    Returns:
    this StringBuilder
    
    Throws:
    
    IndexOutOfBoundsException - if offset, start, or end are out of bounds
  - insert
```
public StringBuilder insert(int offset,
                   char[] data)
```
    Insert the char[] argument into this StringBuilder.
    
    Parameters:
    offset - the place to insert in this buffer
    data - the char[] to insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    NullPointerException - if data is null
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    See Also:
    insert(int, char[], int, int)
  - insert
```
public StringBuilder insert(int offset,
                   boolean bool)
```
    Insert the String value of the argument into this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    offset - the place to insert in this buffer
    bool - the boolean to convert and insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    See Also:
    String.valueOf(boolean)
  - insert
```
public StringBuilder insert(int offset,
                   char ch)
```
    Insert the char argument into this StringBuilder.
    
    Parameters:
    offset - the place to insert in this buffer
    ch - the char to insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
  - insert
```
public StringBuilder insert(int offset,
                   int inum)
```
    Insert the String value of the argument into this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    offset - the place to insert in this buffer
    inum - the int to convert and insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    See Also:
    String.valueOf(int)
  - insert
```
public StringBuilder insert(int offset,
                   long lnum)
```
    Insert the String value of the argument into this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    offset - the place to insert in this buffer
    lnum - the long to convert and insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    See Also:
    String.valueOf(long)
  - insert
```
public StringBuilder insert(int offset,
                   float fnum)
```
    Insert the String value of the argument into this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    offset - the place to insert in this buffer
    fnum - the float to convert and insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    See Also:
    String.valueOf(float)
  - insert
```
public StringBuilder insert(int offset,
                   double dnum)
```
    Insert the String value of the argument into this StringBuilder. Uses String.valueOf() to convert to String.
    
    Parameters:
    offset - the place to insert in this buffer
    dnum - the double to convert and insert
    
    Returns:
    this StringBuilder
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    See Also:
    String.valueOf(double)
  - reverse
```
public StringBuilder reverse()
```
    Reverse the characters in this StringBuilder. The same sequence of characters exists, but in the reverse index ordering.
    
    Returns:
    this StringBuilder
  - toString
```
public String toString()
```
    Convert this StringBuilder to a String. The String is composed of the characters currently in this StringBuilder. Note that the result is a copy, and that future modifications to this buffer do not affect the String.
    
    Specified by:
    
    toString in interface CharSequence
    
    Overrides:
    
    toString in class Object
    
    Returns:
    the characters in this StringBuilder
    See Also:
    Object.getClass(), Object.hashCode(), Class.getName(), Integer.toHexString(int)
  - ensureCapacity
```
public void ensureCapacity(int minimumCapacity)
```
    Increase the capacity of this StringBuffer. This will ensure that an expensive growing operation will not occur until minimumCapacity is reached. The buffer is grown to the larger of minimumCapacity and capacity() * 2 + 2, if it is not already large enough.
    
    Parameters:
    minimumCapacity - the new capacity
    See Also:
    #capacity()
  - setLength
```
public void setLength(int newLength)
```
    Set the length of this StringBuffer. If the new length is greater than the current length, all the new characters are set to '\0'. If the new length is less than the current length, the first newLength characters of the old array will be preserved, and the remaining characters are truncated.
    
    Parameters:
    newLength - the new length
    
    Throws:
    
    IndexOutOfBoundsException - if the new length is negative (while unspecified, this is a StringIndexOutOfBoundsException)
    See Also:
    CharSequence.length()
  - charAt
```
public char charAt(int index)
```
    Get the character at the specified index.
    
    Specified by:
    
    charAt in interface CharSequence
    
    Parameters:
    index - the index of the character to get, starting at 0
    
    Returns:
    the character at the specified index
    
    Throws:
    
    IndexOutOfBoundsException - if index is negative or >= length() (while unspecified, this is a StringIndexOutOfBoundsException)
  - codePointAt
```
public int codePointAt(int index)
```
    Get the code point at the specified index. This is like #charAt(int), but if the character is the start of a surrogate pair, and the following character completes the pair, then the corresponding supplementary code point is returned.
    
    Parameters:
    index - the index of the codepoint to get, starting at 0
    
    Returns:
    the codepoint at the specified index
    
    Throws:
    
    IndexOutOfBoundsException - if index is negative or >= length()
    Since:
    
    1.5
  - codePointBefore
```
public int codePointBefore(int index)
```
    Get the code point before the specified index. This is like #codePointAt(int), but checks the characters at index-1 and index-2 to see if they form a supplementary code point.
    
    Parameters:
    index - the index just past the codepoint to get, starting at 0
    
    Returns:
    the codepoint at the specified index
    
    Throws:
    
    IndexOutOfBoundsException - if index is negative or >= length()
    Since:
    
    1.5
  - getChars
```
public void getChars(int srcOffset,
            int srcEnd,
            char[] dst,
            int dstOffset)
```
    Get the specified array of characters. srcOffset - srcEnd characters will be copied into the array you pass in.
    
    Parameters:
    srcOffset - the index to start copying from (inclusive)
    srcEnd - the index to stop copying from (exclusive)
    dst - the array to copy into
    dstOffset - the index to start copying into
    
    Throws:
    
    NullPointerException - if dst is null
    
    IndexOutOfBoundsException - if any source or target indices are out of range (while unspecified, source problems cause a StringIndexOutOfBoundsException, and dest problems cause an ArrayIndexOutOfBoundsException)
    See Also:
    System.arraycopy(Object, int, Object, int, int)
  - setCharAt
```
public void setCharAt(int index,
             char ch)
```
    Set the character at the specified index.
    
    Parameters:
    index - the index of the character to set starting at 0
    ch - the value to set that character to
    
    Throws:
    
    IndexOutOfBoundsException - if index is negative or >= length() (while unspecified, this is a StringIndexOutOfBoundsException)
  - indexOf
```
public int indexOf(String str)
```
    Finds the first instance of a substring in this StringBuilder.
    
    Parameters:
    str - String to find
    
    Returns:
    location (base 0) of the String, or -1 if not found
    
    Throws:
    
    NullPointerException - if str is null
    See Also:
    indexOf(String, int)
  - indexOf
```
public int indexOf(String str,
          int fromIndex)
```
    Finds the first instance of a String in this StringBuffer, starting at a given index. If starting index is less than 0, the search starts at the beginning of this String. If the starting index is greater than the length of this String, or the substring is not found, -1 is returned.
    
    Parameters:
    str - String to find
    fromIndex - index to start the search
    
    Returns:
    location (base 0) of the String, or -1 if not found
    
    Throws:
    
    NullPointerException - if str is null
    Since:
    
    1.4
  - lastIndexOf
```
public int lastIndexOf(String str)
```
    Finds the last instance of a substring in this StringBuffer.
    
    Parameters:
    str - String to find
    
    Returns:
    location (base 0) of the String, or -1 if not found
    
    Throws:
    
    NullPointerException - if str is null
    Since:
    
    1.4
    
    See Also:
    lastIndexOf(String, int)
  - lastIndexOf
```
public int lastIndexOf(String str,
              int fromIndex)
```
    Finds the last instance of a String in this StringBuffer, starting at a given index. If starting index is greater than the maximum valid index, then the search begins at the end of this String. If the starting index is less than zero, or the substring is not found, -1 is returned.
    
    Parameters:
    str - String to find
    fromIndex - index to start the search
    
    Returns:
    location (base 0) of the String, or -1 if not found
    
    Throws:
    
    NullPointerException - if str is null
    Since:
    
    1.4
  - trimToSize
```
public void trimToSize()
```
    This may reduce the amount of memory used by the StringBuffer, by resizing the internal array to remove unused space. However, this method is not required to resize, so this behavior cannot be relied upon.
    
    Since:
    
    1.5
  - codePointCount
```
public int codePointCount(int start,
                 int end)
```
    Return the number of code points between two indices in the StringBuffer. An unpaired surrogate counts as a code point for this purpose. Characters outside the indicated range are not examined, even if the range ends in the middle of a surrogate pair.
    
    Parameters:
    start - the starting index
    end - one past the ending index
    
    Returns:
    the number of code points
    Since:
    
    1.5
  - offsetByCodePoints
```
public int offsetByCodePoints(int start,
                     int codePoints)
```
    Starting at the given index, this counts forward by the indicated number of code points, and then returns the resulting index. An unpaired surrogate counts as a single code point for this purpose.
    
    Parameters:
    start - the starting index
    codePoints - the number of code points
    
    Returns:
    the resulting index
    Since:
    
    1.5

Class StringBuilder

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.lang.CharSequence

Constructor Detail

StringBuilder

StringBuilder

StringBuilder

StringBuilder

Method Detail

length

capacity

append

append

append

append

append

append

append

append

append

append

append

append

append

appendCodePoint

delete

deleteCharAt

replace

substring

subSequence

substring

insert

insert

insert

insert

insert

insert

insert

insert

insert

insert

insert

insert

reverse

toString

ensureCapacity

setLength

charAt

codePointAt

codePointBefore

getChars

setCharAt

indexOf

indexOf

lastIndexOf

lastIndexOf

trimToSize

codePointCount

offsetByCodePoints