StringBuffer

java.lang.Object
- java.lang.StringBuffer

All Implemented Interfaces:

CharSequence
```
public final class StringBuffer
extends Object
implements CharSequence
```
An expandable string of characters. Actually not very expandable! 09/25/2001 added number formatting thanks to Martin E. Nielsen. You must ensure that the buffer is large enough to take the formatted number.

Author:

Martin E. Nielsen, Sven Köhler

Constructor Summary

Constructors
Constructor and Description

StringBuffer()

StringBuffer(CharSequence seq)

StringBuffer(int length)

StringBuffer(String aString)

Constructors
Constructor and Description
`StringBuffer()`
`StringBuffer(CharSequence seq)`
`StringBuffer(int length)`
`StringBuffer(String aString)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`StringBuffer`	`append(boolean aBoolean)`
`StringBuffer`	`append(char aChar)`
`StringBuffer`	`append(char[] c)`
`StringBuffer`	`append(char[] c, int off, int len)`
`StringBuffer`	`append(CharSequence cs)`
`StringBuffer`	`append(CharSequence cs, int start, int end)`
`StringBuffer`	`append(double aDouble)`
`StringBuffer`	`append(float aFloat)`
`StringBuffer`	`append(int i)`
`StringBuffer`	`append(long aLong)`
`StringBuffer`	`append(Object aObject)`
`StringBuffer`	`append(String s)`
`StringBuffer`	`append(StringBuffer sb)`
`StringBuffer`	`appendCodePoint(int cp)`
`int`	`capacity()`
`char`	`charAt(int i)` Returns the character at the given index.
`StringBuffer`	`delete(int start, int end)`
`StringBuffer`	`deleteCharAt(int index)`
`void`	`ensureCapacity(int minCapacity)`
`void`	`getChars(int start, int end, char[] dst, int dstStart)` Retrieves the contents of the StringBuilder in the form of an array of characters.
`int`	`indexOf(String str)`
`int`	`indexOf(String str, int fromIndex)`
`StringBuffer`	`insert(int offset, char[] data)` Insert the `char[]` argument into this `StringBuffer`.
`StringBuffer`	`insert(int offset, char[] str, int str_offset, int len)` Insert a subarray of the `char[]` argument into this `StringBuffer`.
`StringBuffer`	`insert(int offset, Object obj)` Insert the `String` value of the argument into this `StringBuffer`.
`StringBuffer`	`insert(int offset, String str)` Insert the `String` argument into this `StringBuffer`.
`int`	`lastIndexOf(String str)`
`int`	`lastIndexOf(String str, int fromIndex)`
`int`	`length()` Returns the length of the sequence.
`StringBuffer`	`replace(int start, int end, String str)` Replace characters between index `start` (inclusive) and `end` (exclusive) with `str`.
`StringBuffer`	`reverse()` Reverse the characters in this StringBuffer.
`void`	`setCharAt(int i, char ch)`
`void`	`setLength(int newLen)`
`CharSequence`	`subSequence(int start, int end)` Returns a new `CharSequence` of the indicated range.
`String`	`substring(int start)`
`String`	`substring(int start, int end)`
`String`	`toString()` Returns the complete `CharSequence` as a `String`.
`void`	`trimToSize()`

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

- Constructor Detail
  - StringBuffer
```
public StringBuffer()
```
  - StringBuffer
```
public StringBuffer(CharSequence seq)
```
  - StringBuffer
```
public StringBuffer(int length)
```
  - StringBuffer
```
public StringBuffer(String aString)
```
- Method Detail
  - append
```
public StringBuffer append(boolean aBoolean)
```
  - append
```
public StringBuffer append(char aChar)
```
  - append
```
public StringBuffer append(char[] c)
```
  - append
```
public StringBuffer append(char[] c,
                           int off,
                           int len)
```
  - append
```
public StringBuffer append(CharSequence cs)
```
  - append
```
public StringBuffer append(CharSequence cs,
                           int start,
                           int end)
```
  - append
```
public StringBuffer append(double aDouble)
```
  - append
```
public StringBuffer append(float aFloat)
```
  - append
```
public StringBuffer append(int i)
```
  - append
```
public StringBuffer append(long aLong)
```
  - append
```
public StringBuffer append(Object aObject)
```
  - append
```
public StringBuffer append(String s)
```
  - append
```
public StringBuffer append(StringBuffer sb)
```
  - appendCodePoint
```
public StringBuffer appendCodePoint(int cp)
```
  - capacity
```
public int capacity()
```
  - charAt
```
public char charAt(int i)
```
    Description copied from interface: CharSequence
    
    Returns the character at the given index.
    
    Specified by:
    
    charAt in interface CharSequence
    
    Parameters:
    
    i - the index to retrieve from
    
    Returns:
    
    the character at that location
  - delete
```
public StringBuffer delete(int start,
                           int end)
```
  - deleteCharAt
```
public StringBuffer deleteCharAt(int index)
```
  - ensureCapacity
```
public void ensureCapacity(int minCapacity)
```
  - getChars
```
public void getChars(int start,
                     int end,
                     char[] dst,
                     int dstStart)
```
    Retrieves the contents of the StringBuilder in the form of an array of characters.
  - indexOf
```
public int indexOf(String str)
```
  - indexOf
```
public int indexOf(String str,
                   int fromIndex)
```
  - insert
```
public StringBuffer insert(int offset,
                           char[] data)
```
    Insert the char[] argument into this StringBuffer.
    
    Parameters:
    
    offset - the place to insert in this buffer
    
    data - the char[] to insert
    
    Returns:
    
    this StringBuffer
    
    Throws:
    
    NullPointerException - if data is null
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    
    See Also:
    
    insert(int, char[], int, int)
  - insert
```
public StringBuffer insert(int offset,
                           char[] str,
                           int str_offset,
                           int len)
```
    Insert a subarray of the char[] argument into this StringBuffer.
    
    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 StringBuffer
    
    Throws:
    
    NullPointerException - if str is null
    
    StringIndexOutOfBoundsException - if any index is out of bounds
    
    Since:
    
    1.2
  - insert
```
public StringBuffer insert(int offset,
                           Object obj)
```
    Insert the String value of the argument into this StringBuffer. 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 StringBuffer
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
    
    See Also:
    
    String.valueOf(Object)
  - insert
```
public StringBuffer insert(int offset,
                           String str)
```
    Insert the String argument into this StringBuffer. 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 StringBuffer
    
    Throws:
    
    StringIndexOutOfBoundsException - if offset is out of bounds
  - lastIndexOf
```
public int lastIndexOf(String str)
```
  - lastIndexOf
```
public int lastIndexOf(String str,
                       int fromIndex)
```
  - length
```
public int length()
```
    Description copied from interface: CharSequence
    
    Returns the length of the sequence. This is the number of 16-bit characters in the sequence, which may differ from the length of the underlying encoding.
    
    Specified by:
    
    length in interface CharSequence
    
    Returns:
    
    the sequence length
  - replace
```
public StringBuffer 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 StringBuffer, 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 StringBuffer
    
    Throws:
    
    StringIndexOutOfBoundsException - if start or end are out of bounds
    
    NullPointerException - if str is null
    
    Since:
    
    1.2
  - reverse
```
public StringBuffer reverse()
```
    Reverse the characters in this StringBuffer. The same sequence of characters exists, but in the reverse index ordering.
    
    Returns:
    
    this StringBuffer
  - setCharAt
```
public void setCharAt(int i,
                      char ch)
```
  - setLength
```
public void setLength(int newLen)
```
  - subSequence
```
public CharSequence subSequence(int start,
                                int end)
```
    Description copied from interface: CharSequence
    
    Returns a new CharSequence of the indicated range.
    
    Specified by:
    
    subSequence in interface CharSequence
    
    Parameters:
    
    start - the start index (inclusive)
    
    end - the end index (exclusive)
    
    Returns:
    
    a subsequence of this
  - substring
```
public String substring(int start)
```
  - substring
```
public String substring(int start,
                        int end)
```
  - toString
```
public String toString()
```
    Description copied from interface: CharSequence
    
    Returns the complete CharSequence as a String. Classes that implement this interface should return a String which contains only the characters in the sequence in the correct order.
    
    Specified by:
    
    toString in interface CharSequence
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    the character sequence as a String
  - trimToSize
```
public void trimToSize()
```

Class StringBuffer

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

StringBuffer

StringBuffer

StringBuffer

StringBuffer

Method Detail

append

append

append

append

append

append

append

append

append

append

append

append

append

appendCodePoint

capacity

charAt

delete

deleteCharAt

ensureCapacity

getChars

indexOf

indexOf

insert

insert

insert

insert

lastIndexOf

lastIndexOf

length

replace

reverse

setCharAt

setLength

subSequence

substring

substring

toString

trimToSize