| |||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | ||||
StringBuilder sb = new StringBuilder();
Based on 98 examples
public final class StringBuilder extends AbstractStringBuilder implements Serializable, CharSequence
A mutable sequence of characters. This class provides an API compatible
with StringBuffer, but with no guarantee of synchronization.
This class is designed for use as a drop-in replacement for
StringBuffer in places where the string buffer was being
used by a single thread (as is generally the case). Where possible,
it is recommended that this class be used in preference to
StringBuffer as it will be faster under most implementations.
The principal operations on a StringBuilder are the
append and insert methods, which are
overloaded so as to accept data of any type. Each effectively
converts a given datum to a string and then appends or inserts the
characters of that string to the string builder. The
append method always adds these characters at the end
of the builder; the insert method adds the characters at
a specified point.
For example, if z refers to a string builder object
whose current contents are "start", then
the method call z.append("le") would cause the string
builder to contain "startle", whereas
z.insert(4, "le") would alter the string builder to
contain "starlet".
In general, if sb refers to an instance of a StringBuilder,
then sb.append(x) has the same effect as
sb.insert(sb.length(), x).
Every string builder has a capacity. As long as the length of the
character sequence contained in the string builder does not exceed
the capacity, it is not necessary to allocate a new internal
buffer. If the internal buffer overflows, it is automatically made larger.
Instances of StringBuilder are not safe for
use by multiple threads. If such synchronization is required then it is
recommended that {@link java.lang.StringBuffer} be used.
| Constructor Summary | |
|---|---|
|
Constructs a string builder with no characters in it and an initial capacity of 16 characters. |
|
|
Constructs a string builder that contains the same characters as the specified CharSequence.
|
|
StringBuilder(int capacity)Constructs a string builder with no characters in it and an initial capacity specified by the capacity argument.
|
|
StringBuilder(String str)Constructs a string builder initialized to the contents of the specified string. |
|
| Constructor Detail |
|---|
public StringBuilder()
public StringBuilder(CharSequence seq)
CharSequence. The initial capacity of
the string builder is 16 plus the length of the
CharSequence argument.
seq - the sequence to copy.public StringBuilder(int capacity)
capacity argument.
capacity - the initial capacity.public StringBuilder(String str)
16 plus the length of the string argument.
str - the initial contents of the buffer.| Method Detail |
|---|
public StringBuilder append(boolean b)
append in class AbstractStringBuilderbpublic StringBuilder append(char c)
append in class AbstractStringBuildercpublic StringBuilder append(CharSequence s)
append in class AbstractStringBuilderspublic StringBuilder append(CharSequence s,
int start,
int end)
append in class AbstractStringBuildersstartendpublic StringBuilder append(char[] str)
append in class AbstractStringBuilderstrpublic StringBuilder append(char[] str,
int offset,
int len)
append in class AbstractStringBuilderstroffsetlenpublic StringBuilder append(double d)
append in class AbstractStringBuilderdpublic StringBuilder append(float f)
append in class AbstractStringBuilderfpublic StringBuilder append(int i)
append in class AbstractStringBuilderipublic StringBuilder append(long lng)
append in class AbstractStringBuilderlngpublic StringBuilder append(Object obj)
append in class AbstractStringBuilderobjpublic StringBuilder append(String str)
append in class AbstractStringBuilderstrpublic StringBuilder append(StringBuffer sb)
The characters of the StringBuffer argument are appended, in order, to this sequence, increasing the length of this sequence by the length of the argument. If sb is null, then the four characters "null" are appended to this sequence.
Let n be the length of this character sequence just prior to
execution of the append method. Then the character at index
k in the new character sequence is equal to the character at
index k in the old character sequence, if k is less than
n; otherwise, it is equal to the character at index k-n
in the argument sb.
append in class AbstractStringBuildersb - the StringBuffer to append.public StringBuilder appendCodePoint(int codePoint)
appendCodePoint in class AbstractStringBuildercodePointpublic StringBuilder delete(int start,
int end)
delete in class AbstractStringBuilderstartendpublic StringBuilder deleteCharAt(int index)
deleteCharAt in class AbstractStringBuilderindexpublic int indexOf(String str)
indexOf in class AbstractStringBuilderstrpublic int indexOf(String str,
int fromIndex)
indexOf in class AbstractStringBuilderstrfromIndexpublic StringBuilder insert(int offset,
boolean b)
insert in class AbstractStringBuilderoffsetbpublic StringBuilder insert(int offset,
char c)
insert in class AbstractStringBuilderoffsetcpublic StringBuilder insert(int dstOffset,
CharSequence s)
insert in class AbstractStringBuilderdstOffsetspublic StringBuilder insert(int dstOffset,
CharSequence s,
int start,
int end)
insert in class AbstractStringBuilderdstOffsetsstartendpublic StringBuilder insert(int offset,
char[] str)
insert in class AbstractStringBuilderoffsetstrpublic StringBuilder insert(int index,
char[] str,
int offset,
int len)
insert in class AbstractStringBuilderindexstroffsetlenpublic StringBuilder insert(int offset,
double d)
insert in class AbstractStringBuilderoffsetdpublic StringBuilder insert(int offset,
float f)
insert in class AbstractStringBuilderoffsetfpublic StringBuilder insert(int offset,
int i)
insert in class AbstractStringBuilderoffsetipublic StringBuilder insert(int offset,
long l)
insert in class AbstractStringBuilderoffsetlpublic StringBuilder insert(int offset,
Object obj)
insert in class AbstractStringBuilderoffsetobjpublic StringBuilder insert(int offset,
String str)
insert in class AbstractStringBuilderoffsetstrpublic int lastIndexOf(String str)
lastIndexOf in class AbstractStringBuilderstrpublic int lastIndexOf(String str,
int fromIndex)
lastIndexOf in class AbstractStringBuilderstrfromIndexpublic StringBuilder replace(int start,
int end,
String str)
replace in class AbstractStringBuilderstartendstrpublic StringBuilder reverse()
reverse in class AbstractStringBuilderpublic String toString()
toString in class AbstractStringBuilder
| |||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | ||||