String class « String « Character String « Development

Type	Field	Summary
static Comparator<String>	CASE_INSENSITIVE_ORDER	A Comparator that orders String objects as by compareToIgnoreCase.

Create string objects

Constructor	Summary
String()	Creates empty string
String(byte[] bytes)	Creates a String from specified array of bytes using the platform's default charset.
String(byte[] bytes, Charset charset)	Creates a String by decoding the bytes using the specified charset.
String(byte[] bytes, int offset, int length)	Creates a String by decoding the subarray of bytes using the platform's default charset.
String(byte[] bytes, int offset, int length, Charset charset)	Creates a new String by decoding the specified subarray of bytes using the specified charset.
String(byte[] bytes, int offset, int length, String charsetName)	Creates a String by decoding the subarray of bytes using the specified charset.
String(byte[] bytes, String charsetName)	Creates a String by decoding the array of bytes using the specified charset.
String(char[] value)	Creates a String from the character array argument.
String(char[] value, int offset, int count)	Creates a new String from a subarray of char array argument.
String(int[] codePoints, int offset, int count)	Creates a new String that contains characters from a subarray of the Unicode code point array argument.
String(String original)	Initializes a newly created String object so that it represents the same sequence of characters as the argument; in other words, the newly created string is a copy of the argument string.
String(StringBuffer buffer)	Creates a new string that contains the sequence of characters currently contained in the string buffer argument.
String(StringBuilder builder)	Creates a new string that contains the sequence of characters currently contained in the string builder argument.

Get a single char by index

Return	Method	Summary
char	charAt(int index)	Returns the char value at the specified index.

Compare two string value

Return	Method	Summary
int	compareTo(String anotherString)	Compares two strings lexicographically.
int	compareToIgnoreCase(String str)	Compares two strings lexicographically, ignoring case differences.
boolean	equals(Object anObject)	Compares this string to the specified object.
boolean	equalsIgnoreCase(String anotherString)	Compares this String to another String, ignoring case considerations.

Search a sub string inside a string

boolean	contains(CharSequence s)	Returns true if and only if this string contains the specified sequence of char values.
boolean	contentEquals(CharSequence cs)	Compares this string to the specified CharSequence.
boolean	contentEquals(StringBuffer sb)	Compares this string to the specified StringBuffer.
int	indexOf(int ch)	Returns the index within this string of the first occurrence of the specified character.
int	indexOf(int ch, int fromIndex)	Returns the index within this string of the first occurrence of the specified character, starting the search at the specified index.
int	indexOf(String str)	Returns the index within this string of the first occurrence of the specified substring.
int	indexOf(String str, int fromIndex)	Returns the index within this string of the first occurrence of the specified substring, starting at the specified index.
int	lastIndexOf(int ch)	Returns the index within this string of the last occurrence of the specified character.
int	lastIndexOf(int ch, int fromIndex)	Returns the index within this string of the last occurrence of the specified character, searching backward starting at the specified index.
int	lastIndexOf(String str)	Returns the index within this string of the rightmost occurrence of the specified substring.
int	lastIndexOf(String str, int fromIndex)	Returns the index within this string of the last occurrence of the specified substring, searching backward starting at the specified index.
boolean	startsWith(String prefix)	Tests if this string starts with the specified prefix.
boolean	startsWith(String prefix, int toffset)	Tests if the substring of this string beginning at the specified index starts with the specified prefix.
boolean	endsWith(String suffix)	Tests if this string ends with the specified suffix.

Format a string

Return	Method	Summary
static String	format(Locale l, String format, Object... args)	Returns a formatted string using the specified locale, format string, and arguments.
static String	format(String format, Object... args)	Returns a formatted string using the specified format string and arguments.

Trim, concat and intern a string

Return	Method	Summary
String	concat(String str)	Concatenates the specified string to the end of this string.
String	trim()	Returns a copy of the string, with leading and trailing whitespace omitted.
String	intern()	Returns a canonical representation for the string object.

Get byte array from string

Return	Method	Summary
byte[]	getBytes()	Encodes this String into a sequence of bytes using the platform's default charset, storing the result into a new byte array.
byte[]	getBytes(Charset charset)	Encodes this String into a sequence of bytes using the given charset, storing the result into a new byte array.
byte[]	getBytes(String charsetName)	Encodes this String into a sequence of bytes using the named charset, storing the result into a new byte array.

Get char array from string

Return	Method	Summary
static String	copyValueOf(char[] data)	Returns a String that represents the character sequence in the array specified.
static String	copyValueOf(char[] data, int offset, int count)	Returns a String that represents the character sequence in the array specified.
void	getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)	Copies characters from this string into the destination character array.
char[]	toCharArray()	Converts this string to a new character array.

Check string length and if it is empty

Return	Method	Summary
boolean	isEmpty()	Returns true if, and only if, length() is 0.
int	length()	Returns the length of this string.

Match or replace a string

Return	Method	Summary
boolean	matches(String regex)	Tells whether or not this string matches the given regular expression.
boolean	regionMatches(boolean ignoreCase, int toffset, String other, int ooffset, int len)	Tests if two string regions are equal.
boolean	regionMatches(int toffset, String other, int ooffset, int len)	Tests if two string regions are equal.
String	replace(char oldChar, char newChar)	Returns a new string resulting from replacing all occurrences of oldChar in this string with newChar.
String	replace(CharSequence target, CharSequence replacement)	Replaces each substring of this string that matches the literal target sequence with the specified literal replacement sequence.
String	replaceAll(String regex, String replacement)	Replaces each substring of this string that matches the given regular expression with the given replacement.
String	replaceFirst(String regex, String replacement)	Replaces the first substring of this string that matches the given regular expression with the given replacement.
String[]	split(String regex)	Splits this string around matches of the given regular expression.
String[]	split(String regex, int limit)	Splits this string around matches of the given regular expression.

Get sub string from a string

Return	Method	Summary
CharSequence	subSequence(int beginIndex, int endIndex)	Returns a new character sequence that is a subsequence of this sequence.
String	substring(int beginIndex)	Returns a new string that is a substring of this string.
String	substring(int beginIndex, int endIndex)	Returns a new string that is a substring of this string.

Convert string case

Return	Method	Summary
String	toLowerCase()	Converts this String to lower case using the rules of the default locale.
String	toLowerCase(Locale locale)	Converts this String to lower case using the rules of the given Locale.
String	toUpperCase()	Converts this String to upper case using the rules of the default locale.
String	toUpperCase(Locale locale)	Converts this String to upper case using the rules of the given Locale.

Convert boolean, char, double, float,int,long,object to String

Return	Method	Summary
static String	valueOf(boolean b)	Returns the string representation of the boolean argument.
static String	valueOf(char c)	Returns the string representation of the char argument.
static String	valueOf(char[] data)	Returns the string representation of the char array argument.
static String	valueOf(char[] data, int offset, int count)	Returns the string representation of a specific subarray of the char array argument.
static String	valueOf(double d)	Returns the string representation of the double argument.
static String	valueOf(float f)	Returns the string representation of the float argument.
static String	valueOf(int i)	Returns the string representation of the int argument.
static String	valueOf(long l)	Returns the string representation of the long argument.
static String	valueOf(Object obj)	Returns the string representation of the Object argument.