public class StringBuilder extends Object implements Appendable, CharSequence
StringBuilder that implements equals and hashcode.CharSequence,
Appendable,
StringBuilder,
String| Constructor and Description |
|---|
StringBuilder()
Constructs an instance with an initial capacity of
16. |
StringBuilder(CharSequence seq)
Constructs an instance that's initialized with the contents of the specified
CharSequence. |
StringBuilder(int capacity)
Constructs an instance with the specified capacity.
|
StringBuilder(String string)
Constructs an instance that's initialized with the contents of the specified
String. |
StringBuilder(StringBuilder builder) |
| Modifier and Type | Method and Description |
|---|---|
StringBuilder |
append(boolean b)
Appends the string representation of the specified
boolean value. |
StringBuilder |
append(char c)
Appends the string representation of the specified
char value. |
StringBuilder |
append(char[] ch)
Appends the string representation of the specified
char[]. |
StringBuilder |
append(char[] str,
int offset,
int len)
Appends the string representation of the specified subset of the
char[]. |
StringBuilder |
append(CharSequence csq)
Appends the string representation of the specified
CharSequence. |
StringBuilder |
append(CharSequence csq,
int start,
int end)
Appends the string representation of the specified subsequence of the
CharSequence. |
StringBuilder |
append(double d)
Appends the string representation of the specified
double value. |
StringBuilder |
append(float f)
Appends the string representation of the specified
float value. |
StringBuilder |
append(int value)
Appends the string representation of the specified
int value. |
StringBuilder |
append(int value,
int minLength)
Appends the string representation of the specified
int value. |
StringBuilder |
append(int value,
int minLength,
char prefix)
Appends the string representation of the specified
int value. |
StringBuilder |
append(long value)
Appends the string representation of the specified
long value. |
StringBuilder |
append(long value,
int minLength)
Appends the string representation of the specified
long value. |
StringBuilder |
append(long value,
int minLength,
char prefix)
Appends the string representation of the specified
long value. |
StringBuilder |
append(Object obj)
Appends the string representation of the specified
Object. |
StringBuilder |
append(String str)
Appends the contents of the specified string.
|
StringBuilder |
append(StringBuilder builder) |
StringBuilder |
append(StringBuilder builder,
int start,
int end) |
StringBuilder |
appendCodePoint(int codePoint)
Appends the encoded Unicode code point.
|
StringBuilder |
appendLine(String str)
Appends the contents of the specified string, then create a new line.
|
int |
capacity()
Returns the number of characters that can be held without growing.
|
char |
charAt(int index)
Retrieves the character at the
index. |
void |
clear()
Sets length to 0.
|
int |
codePointAt(int index)
Retrieves the Unicode code point value at the
index. |
int |
codePointBefore(int index)
Retrieves the Unicode code point value that precedes the
index. |
int |
codePointCount(int beginIndex,
int endIndex)
Calculates the number of Unicode code points between
beginIndex and endIndex. |
boolean |
contains(String subString) |
boolean |
containsIgnoreCase(String subString) |
StringBuilder |
delete(int start,
int end)
Deletes a sequence of characters specified by
start and end. |
StringBuilder |
deleteCharAt(int index)
Deletes the character at the specified index.
|
void |
ensureCapacity(int min)
Ensures that this object has a minimum capacity available before requiring the internal buffer to be enlarged.
|
boolean |
equals(Object obj) |
boolean |
equalsIgnoreCase(String other) |
boolean |
equalsIgnoreCase(StringBuilder other) |
void |
getChars(int start,
int end,
char[] dest,
int destStart)
Copies the requested sequence of characters to the
char[] passed starting at destStart. |
int |
hashCode() |
int |
indexOf(String string)
Searches for the first index of the specified character.
|
int |
indexOf(String subString,
int start)
Searches for the index of the specified character.
|
int |
indexOfIgnoreCase(String subString,
int start) |
StringBuilder |
insert(int offset,
boolean b)
Inserts the string representation of the specified
boolean value at the specified offset. |
StringBuilder |
insert(int offset,
char c)
Inserts the string representation of the specified
char value at the specified offset. |
StringBuilder |
insert(int offset,
char[] ch)
Inserts the string representation of the specified
char[] at the specified offset. |
StringBuilder |
insert(int offset,
char[] str,
int strOffset,
int strLen)
Inserts the string representation of the specified subsequence of the
char[] at the specified offset. |
StringBuilder |
insert(int offset,
CharSequence s)
Inserts the string representation of the specified
CharSequence at the specified offset. |
StringBuilder |
insert(int offset,
CharSequence s,
int start,
int end)
Inserts the string representation of the specified subsequence of the
CharSequence at the specified offset. |
StringBuilder |
insert(int offset,
double d)
Inserts the string representation of the specified
double value at the specified offset. |
StringBuilder |
insert(int offset,
float f)
Inserts the string representation of the specified
float value at the specified offset. |
StringBuilder |
insert(int offset,
int i)
Inserts the string representation of the specified
int value at the specified offset. |
StringBuilder |
insert(int offset,
long l)
Inserts the string representation of the specified
long value at the specified offset. |
StringBuilder |
insert(int offset,
Object obj)
Inserts the string representation of the specified
Object at the specified offset. |
StringBuilder |
insert(int offset,
String str)
Inserts the specified string at the specified
offset. |
int |
lastIndexOf(String string)
Searches for the last index of the specified character.
|
int |
lastIndexOf(String subString,
int start)
Searches for the index of the specified character.
|
int |
length()
The current length.
|
static int |
numChars(int value,
int radix) |
static int |
numChars(long value,
int radix) |
int |
offsetByCodePoints(int index,
int codePointOffset)
Returns the index that is offset
codePointOffset code points from index. |
StringBuilder |
replace(char find,
String replace)
Replaces all instances of
find with replace. |
StringBuilder |
replace(int start,
int end,
String str)
Replaces the specified subsequence in this builder with the specified string.
|
StringBuilder |
replace(String find,
String replace)
Replaces all instances of
find with replace. |
StringBuilder |
reverse()
Reverses the order of characters in this builder.
|
void |
setCharAt(int index,
char ch)
Sets the character at the
index. |
void |
setLength(int newLength)
Sets the current length to a new value.
|
CharSequence |
subSequence(int start,
int end)
Returns a
CharSequence of the subsequence from the start index to the end index. |
String |
substring(int start)
Returns the String value of the subsequence from the
start index to the current end. |
String |
substring(int start,
int end)
Returns the String value of the subsequence from the
start index to the end index. |
String |
toString()
Returns the current String representation.
|
void |
trimToSize()
Trims off any extra capacity beyond the current length.
|
chars, codePointspublic StringBuilder()
16.capacity()public StringBuilder(int capacity)
capacity - the initial capacity to use.NegativeArraySizeException - if the specified capacity is negative.capacity()public StringBuilder(CharSequence seq)
CharSequence. The capacity of the new
builder will be the length of the CharSequence plus 16.seq - the CharSequence to copy into the builder.NullPointerException - if seq is null.public StringBuilder(StringBuilder builder)
public StringBuilder(String string)
String. The capacity of the new
builder will be the length of the String plus 16.string - the String to copy into the builder.NullPointerException - if str is null.public static int numChars(int value,
int radix)
public static int numChars(long value,
int radix)
public int capacity()
ensureCapacity(int),
lengthpublic char charAt(int index)
index.charAt in interface CharSequenceindex - the index of the character to retrieve.IndexOutOfBoundsException - if index is negative or greater than or equal to the current length().public void ensureCapacity(int min)
minimumCapacity is larger than the current capacity(), then the
capacity will be increased to the largest value of either the minimumCapacity or the current capacity multiplied by
two plus two. Although this is the general policy, there is no guarantee that the capacity will change.min - the new minimum capacity to set.public void getChars(int start,
int end,
char[] dest,
int destStart)
char[] passed starting at destStart.start - the inclusive start index of the characters to copy.end - the exclusive end index of the characters to copy.dest - the char[] to copy the characters to.destStart - the inclusive start index of dest to begin copying to.IndexOutOfBoundsException - if the start is negative, the destStart is negative, the start is
greater than end, the end is greater than the current length() or
destStart + end - begin is greater than dest.length.public int length()
length in interface CharSequencepublic void setCharAt(int index,
char ch)
index.index - the zero-based index of the character to replace.ch - the character to set.IndexOutOfBoundsException - if index is negative or greater than or equal to the current length().public void setLength(int newLength)
char value of .newLength - the new length of this StringBuilder.IndexOutOfBoundsException - if length < 0.lengthpublic String substring(int start)
start index to the current end.start - the inclusive start index to begin the subsequence.StringIndexOutOfBoundsException - if start is negative or greater than the current length().public String substring(int start, int end)
start index to the end index.start - the inclusive start index to begin the subsequence.end - the exclusive end index to end the subsequence.StringIndexOutOfBoundsException - if start is negative, greater than end or if end is greater
than the current length().public String toString()
toString in interface CharSequencetoString in class Objectpublic CharSequence subSequence(int start, int end)
CharSequence of the subsequence from the start index to the end index.subSequence in interface CharSequencestart - the inclusive start index to begin the subsequence.end - the exclusive end index to end the subsequence.IndexOutOfBoundsException - if start is negative, greater than end or if end is greater than
the current length().public int indexOf(String string)
string - the string to find.lastIndexOf(String)public int indexOf(String subString, int start)
subString - the string to find.start - the starting offset.lastIndexOf(String,int)public int indexOfIgnoreCase(String subString, int start)
public boolean contains(String subString)
public boolean containsIgnoreCase(String subString)
public int lastIndexOf(String string)
string - the string to find.NullPointerException - if string is null.String.lastIndexOf(java.lang.String)public int lastIndexOf(String subString, int start)
subString - the string to find.start - the starting offset.NullPointerException - if subString is null.String.lastIndexOf(String,int)public void trimToSize()
public int codePointAt(int index)
index.index - the index to the char code unit.IndexOutOfBoundsException - if index is negative or greater than or equal to length().Character,
Character.codePointAt(char[], int, int)public int codePointBefore(int index)
index.index - the index to the char code unit within this object.IndexOutOfBoundsException - if index is less than 1 or greater than length().Character,
Character.codePointBefore(char[], int, int)public int codePointCount(int beginIndex,
int endIndex)
beginIndex and endIndex.beginIndex - the inclusive beginning index of the subsequence.endIndex - the exclusive end index of the subsequence.IndexOutOfBoundsException - if beginIndex is negative or greater than endIndex or endIndex is
greater than length().Character,
Character.codePointCount(char[], int, int)public int offsetByCodePoints(int index,
int codePointOffset)
codePointOffset code points from index.index - the index to calculate the offset from.codePointOffset - the number of code points to count.codePointOffset code points away from index.IndexOutOfBoundsException - if index is negative or greater than length() or if there aren't enough
code points before or after index to match codePointOffset.Character,
Character.offsetByCodePoints(char[], int, int, int, int)public StringBuilder append(boolean b)
boolean value. The boolean value is converted to a
String according to the rule defined by String.valueOf(boolean).b - the boolean value to append.String.valueOf(boolean)public StringBuilder append(char c)
char value. The char value is converted to a string
according to the rule defined by String.valueOf(char).append in interface Appendablec - the char value to append.String.valueOf(char)public StringBuilder append(int value)
int value. The int value is converted to a string
without memory allocation.value - the int value to append.String.valueOf(int)public StringBuilder append(int value, int minLength)
int value. The int value is converted to a string
without memory allocation.value - the int value to append.minLength - the minimum number of characters to addString.valueOf(int)public StringBuilder append(int value, int minLength, char prefix)
int value. The int value is converted to a string
without memory allocation.value - the int value to append.minLength - the minimum number of characters to addprefix - the character to use as prefixString.valueOf(int)public StringBuilder append(long value)
long value. The long value is converted to a string
without memory allocation.value - the long value.public StringBuilder append(long value, int minLength)
long value. The long value is converted to a string
without memory allocation.value - the long value.minLength - the minimum number of characters to addpublic StringBuilder append(long value, int minLength, char prefix)
long value. The long value is converted to a string
without memory allocation.value - the long value.minLength - the minimum number of characters to addprefix - the character to use as prefixpublic StringBuilder append(float f)
float value. The float value is converted to a string
according to the rule defined by String.valueOf(float).f - the float value to append.public StringBuilder append(double d)
double value. The double value is converted to a string
according to the rule defined by String.valueOf(double).d - the double value to append.String.valueOf(double)public StringBuilder append(Object obj)
Object. The Object value is converted to a string
according to the rule defined by String.valueOf(Object).obj - the Object to append.String.valueOf(Object)public StringBuilder append(String str)
null, then the string "null" is appended.str - the string to append.public StringBuilder appendLine(String str)
null, then the string
"null" is appended.str - the string to append.public StringBuilder append(char[] ch)
char[]. The char[] is converted to a string according to
the rule defined by String.valueOf(char[]).ch - the char[] to append..String.valueOf(char[])public StringBuilder append(char[] str, int offset, int len)
char[]. The char[] value is converted to a
String according to the rule defined by String.valueOf(char[],int,int).str - the char[] to append.offset - the inclusive offset index.len - the number of characters.ArrayIndexOutOfBoundsException - if offset and len do not specify a valid subsequence.String.valueOf(char[],int,int)public StringBuilder append(CharSequence csq)
CharSequence. If the CharSequence is null, then
the string "null" is appended.append in interface Appendablecsq - the CharSequence to append.public StringBuilder append(StringBuilder builder)
public StringBuilder append(CharSequence csq, int start, int end)
CharSequence. If the CharSequence is
null, then the string "null" is used to extract the subsequence from.append in interface Appendablecsq - the CharSequence to append.start - the beginning index.end - the ending index.IndexOutOfBoundsException - if start or end are negative, start is greater than end or
end is greater than the length of csq.public StringBuilder append(StringBuilder builder, int start, int end)
public StringBuilder appendCodePoint(int codePoint)
char[] as defined by
Character.toChars(int).codePoint - the Unicode code point to encode and append.Character.toChars(int)public StringBuilder delete(int start, int end)
start and end. Shifts any remaining characters to the left.start - the inclusive start index.end - the exclusive end index.StringIndexOutOfBoundsException - if start is less than zero, greater than the current length or greater than
end.public StringBuilder deleteCharAt(int index)
index - the index of the character to delete.StringIndexOutOfBoundsException - if index is less than zero or is greater than or equal to the current
length.public void clear()
public StringBuilder insert(int offset, boolean b)
boolean value at the specified offset. The
boolean value is converted to a string according to the rule defined by String.valueOf(boolean).offset - the index to insert at.b - the boolean value to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current length.String.valueOf(boolean)public StringBuilder insert(int offset, char c)
char value at the specified offset. The char
value is converted to a string according to the rule defined by String.valueOf(char).offset - the index to insert at.c - the char value to insert.IndexOutOfBoundsException - if offset is negative or greater than the current length().String.valueOf(char)public StringBuilder insert(int offset, int i)
int value at the specified offset. The int value
is converted to a String according to the rule defined by String.valueOf(int).offset - the index to insert at.i - the int value to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current length().String.valueOf(int)public StringBuilder insert(int offset, long l)
long value at the specified offset. The long
value is converted to a String according to the rule defined by String.valueOf(long).offset - the index to insert at.l - the long value to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current {code length()}.String.valueOf(long)public StringBuilder insert(int offset, float f)
float value at the specified offset. The float
value is converted to a string according to the rule defined by String.valueOf(float).offset - the index to insert at.f - the float value to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current length().String.valueOf(float)public StringBuilder insert(int offset, double d)
double value at the specified offset. The double
value is converted to a String according to the rule defined by String.valueOf(double).offset - the index to insert at.d - the double value to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current length().String.valueOf(double)public StringBuilder insert(int offset, Object obj)
Object at the specified offset. The Object value
is converted to a String according to the rule defined by String.valueOf(Object).offset - the index to insert at.obj - the Object to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current length().String.valueOf(Object)public StringBuilder insert(int offset, String str)
offset. If the specified string is null, then the String
"null" is inserted.offset - the index to insert at.str - the String to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current length().public StringBuilder insert(int offset, char[] ch)
char[] at the specified offset. The char[] value
is converted to a String according to the rule defined by String.valueOf(char[]).offset - the index to insert at.ch - the char[] to insert.StringIndexOutOfBoundsException - if offset is negative or greater than the current length().String.valueOf(char[])public StringBuilder insert(int offset, char[] str, int strOffset, int strLen)
char[] at the specified offset. The
char[] value is converted to a String according to the rule defined by String.valueOf(char[],int,int).offset - the index to insert at.str - the char[] to insert.strOffset - the inclusive index.strLen - the number of characters.StringIndexOutOfBoundsException - if offset is negative or greater than the current length(), or
strOffset and strLen do not specify a valid subsequence.String.valueOf(char[],int,int)public StringBuilder insert(int offset, CharSequence s)
CharSequence at the specified offset. The
CharSequence is converted to a String as defined by CharSequence.toString(). If s is null,
then the String "null" is inserted.offset - the index to insert at.s - the CharSequence to insert.IndexOutOfBoundsException - if offset is negative or greater than the current length().CharSequence.toString()public StringBuilder insert(int offset, CharSequence s, int start, int end)
CharSequence at the specified offset.
The CharSequence is converted to a String as defined by CharSequence.subSequence(int, int). If the
CharSequence is null, then the string "null" is used to determine the subsequence.offset - the index to insert at.s - the CharSequence to insert.start - the start of the subsequence of the character sequence.end - the end of the subsequence of the character sequence.IndexOutOfBoundsException - if offset is negative or greater than the current length(), or
start and end do not specify a valid subsequence.CharSequence.subSequence(int, int)public StringBuilder replace(int start, int end, String str)
start - the inclusive begin index.end - the exclusive end index.str - the replacement string.StringIndexOutOfBoundsException - if start is negative, greater than the current length() or greater
than end.NullPointerException - if str is null.public StringBuilder replace(String find, String replace)
find with replace.public StringBuilder replace(char find, String replace)
find with replace.public StringBuilder reverse()
public boolean equalsIgnoreCase(StringBuilder other)
other - May be null.public boolean equalsIgnoreCase(String other)
other - May be null.Copyright © 2019. All rights reserved.