Android APIs
public final class

String

extends Object
implements Serializable Comparable<String> CharSequence
java.lang.Object
   ↳ java.lang.String

Class Overview

An immutable sequence of UTF-16 chars. See Character for details about the relationship between char and Unicode code points.

Summary

Fields
public static final Comparator<String> CASE_INSENSITIVE_ORDER Compares strings using compareToIgnoreCase(String).
Public Constructors
String()
Creates an empty string.
String(byte[] data)
Converts the byte array to a string using the system's default charset.
String(byte[] data, int high)
This constructor was deprecated in API level 1. Use String(byte[]) or String(byte[], String) instead.
String(byte[] data, int offset, int byteCount)
Converts a subsequence of the byte array to a string using the system's default charset.
String(byte[] data, int high, int offset, int byteCount)
This constructor was deprecated in API level 1. Use String(byte[], int, int) instead.
String(byte[] data, int offset, int byteCount, String charsetName)
Converts the byte array to a string using the named charset.
String(byte[] data, String charsetName)
Converts the byte array to a string using the named charset.
String(byte[] data, int offset, int byteCount, Charset charset)
Converts the byte array to a string using the given charset.
String(byte[] data, Charset charset)
Converts the byte array to a String using the given charset.
String(char[] data)
Initializes this string to contain the given chars.
String(char[] data, int offset, int charCount)
Initializes this string to contain the given chars.
String(String toCopy)
Constructs a new string with the same sequence of characters as toCopy.
String(StringBuffer stringBuffer)
Creates a String from the contents of the specified StringBuffer.
String(int[] codePoints, int offset, int count)
Creates a String from the sub-array of Unicode code points.
String(StringBuilder stringBuilder)
Creates a String from the contents of the specified StringBuilder.
Public Methods
char charAt(int index)
Returns the char at index.
int codePointAt(int index)
Returns the Unicode code point at the given index.
int codePointBefore(int index)
Returns the Unicode code point that precedes the given index.
int codePointCount(int start, int end)
Calculates the number of Unicode code points between start and end.
int compareTo(String string)
Compares this string to the given string.
int compareToIgnoreCase(String string)
Compares this string to the given string, ignoring case differences.
String concat(String string)
Concatenates this string and the specified string.
boolean contains(CharSequence cs)
Returns true if this string contains the charss from the given CharSequence.
boolean contentEquals(CharSequence cs)
Returns true if the chars in the given CharSequence are the same as those in this string.
boolean contentEquals(StringBuffer sb)
Returns true if the chars in the given StringBuffer are the same as those in this string.
static String copyValueOf(char[] data, int start, int length)
Creates a new string by copying the given subsequence of the given char[].
static String copyValueOf(char[] data)
Creates a new string by copying the given char[].
boolean endsWith(String suffix)
Compares the specified string to this string to determine if the specified string is a suffix.
boolean equals(Object other)
Compares the given object to this string and returns true if they are equal.
boolean equalsIgnoreCase(String string)
Compares the given string to this string ignoring case.
static String format(Locale locale, String format, Object... args)
Returns a formatted string, using the supplied format and arguments, localized to the given locale.
static String format(String format, Object... args)
Returns a localized formatted string, using the supplied format and arguments, using the user's default locale.
void getBytes(int start, int end, byte[] data, int index)
This method was deprecated in API level 1. Use getBytes() or getBytes(String)
byte[] getBytes(String charsetName)
Returns a new byte array containing the code points of this string encoded using the named charset.
byte[] getBytes(Charset charset)
Returns a new byte array containing the code points of this string encoded using the given charset.
byte[] getBytes()
Returns a new byte array containing the code points in this string encoded using the system's default charset.
void getChars(int start, int end, char[] buffer, int index)
Copies the given subsequence of this string to the given array starting at the given offset.
int hashCode()
Returns an integer hash code for this object.
int indexOf(int c)
Returns the first index of the given code point, or -1.
int indexOf(int c, int start)
Returns the next index of the given code point, or -1.
int indexOf(String subString, int start)
Returns the next index of the given string in this string, or -1.
int indexOf(String string)
Returns the first index of the given string, or -1.
String intern()
Returns an interned string equal to this string.
boolean isEmpty()
Returns true if the length of this string is 0.
int lastIndexOf(String string)
Returns the index of the start of the last match for the given string in this string, or -1.
int lastIndexOf(int c, int start)
Returns the last index of the code point c, or -1.
int lastIndexOf(int c)
Returns the last index of the code point c, or -1.
int lastIndexOf(String subString, int start)
Returns the index of the start of the previous match for the given string in this string, or -1.
int length()
Returns the number of chars in this string.
boolean matches(String regularExpression)
Tests whether this string matches the given regularExpression.
int offsetByCodePoints(int index, int codePointOffset)
Returns the index within this object that is offset from index by codePointOffset code points.
boolean regionMatches(boolean ignoreCase, int thisStart, String string, int start, int length)
Returns true if the given subsequence of the given string matches this string starting at the given offset.
boolean regionMatches(int thisStart, String string, int start, int length)
Returns true if the given subsequence of the given string matches this string starting at the given offset.
String replace(CharSequence target, CharSequence replacement)
Returns a copy of this string after replacing occurrences of target replaced with replacement.
String replace(char oldChar, char newChar)
Returns a copy of this string after replacing occurrences of the given char with another.
String replaceAll(String regularExpression, String replacement)
Replaces all matches for regularExpression within this string with the given replacement.
String replaceFirst(String regularExpression, String replacement)
Replaces the first match for regularExpression within this string with the given replacement.
String[] split(String regularExpression)
Splits this string using the supplied regularExpression.
String[] split(String regularExpression, int limit)
Splits this string using the supplied regularExpression.
boolean startsWith(String prefix)
Compares the specified string to this string to determine if the specified string is a prefix.
boolean startsWith(String prefix, int start)
Compares the specified string to this string, starting at the specified offset, to determine if the specified string is a prefix.
CharSequence subSequence(int start, int end)
Equivalent to substring(int, int) but needed to implement CharSequence.
String substring(int start)
Returns a string containing a suffix of this string starting at start.
String substring(int start, int end)
Returns a string containing the given subsequence of this string.
char[] toCharArray()
Returns a new char array containing a copy of the chars in this string.
String toLowerCase(Locale locale)
Converts this string to lower case, using the rules of locale.
String toLowerCase()
Converts this string to lower case, using the rules of the user's default locale.
String toString()
Returns this string.
String toUpperCase(Locale locale)
Converts this this string to upper case, using the rules of locale.
String toUpperCase()
Converts this this string to upper case, using the rules of the user's default locale.
String trim()
Returns a string with no code points <= \\u0020 at the beginning or end.
static String valueOf(long value)
Returns the string representation of the given long.
static String valueOf(Object value)
Converts the specified object to its string representation.
static String valueOf(char[] data)
Returns a new string containing the same chars as the given array.
static String valueOf(double value)
Returns the string representation of the given double.
static String valueOf(int value)
Returns the string representation of the given int.
static String valueOf(float value)
Returns the string representation of the given float.
static String valueOf(char[] data, int start, int length)
Returns a new string containing the same chars as the given subset of the given array.
static String valueOf(boolean value)
Converts the specified boolean to its string representation.
static String valueOf(char value)
Returns a new string of just the given char.
[Expand]
Inherited Methods
From class java.lang.Object
From interface java.lang.Comparable
From interface java.lang.CharSequence

Fields

public static final Comparator<String> CASE_INSENSITIVE_ORDER

Added in API level 1

Compares strings using compareToIgnoreCase(String). This is not suitable for case-insensitive string comparison for all locales. Use a Collator instead.

Public Constructors

public String ()

Added in API level 1

Creates an empty string.

public String (byte[] data)

Added in API level 1

Converts the byte array to a string using the system's default charset.

Parameters
data

public String (byte[] data, int high)

Added in API level 1

This constructor was deprecated in API level 1.
Use String(byte[]) or String(byte[], String) instead.

Converts the byte array to a string, setting the high byte of every char to the specified value.

Parameters
data the byte array to convert to a string.
high the high byte to use.
Throws
NullPointerException if data == null.

public String (byte[] data, int offset, int byteCount)

Added in API level 1

Converts a subsequence of the byte array to a string using the system's default charset.

Parameters
data
offset
byteCount
Throws
NullPointerException if data == null.
IndexOutOfBoundsException if byteCount < 0 || offset < 0 || offset + byteCount > data.length.

public String (byte[] data, int high, int offset, int byteCount)

Added in API level 1

This constructor was deprecated in API level 1.
Use String(byte[], int, int) instead.

Converts the byte array to a string, setting the high byte of every char to high.

Parameters
data
high
offset
byteCount
Throws
NullPointerException if data == null.
IndexOutOfBoundsException if byteCount < 0 || offset < 0 || offset + byteCount > data.length

public String (byte[] data, int offset, int byteCount, String charsetName)

Added in API level 1

Converts the byte array to a string using the named charset.

The behavior when the bytes cannot be decoded by the named charset is unspecified. Use CharsetDecoder for more control.

Parameters
data
offset
byteCount
charsetName
Throws
NullPointerException if data == null.
IndexOutOfBoundsException if byteCount < 0 || offset < 0 || offset + byteCount > data.length.
UnsupportedEncodingException if the named charset is not supported.

public String (byte[] data, String charsetName)

Added in API level 1

Converts the byte array to a string using the named charset.

The behavior when the bytes cannot be decoded by the named charset is unspecified. Use CharsetDecoder for more control.

Parameters
data
charsetName
Throws
NullPointerException if data == null.
UnsupportedEncodingException if charsetName is not supported.

public String (byte[] data, int offset, int byteCount, Charset charset)

Added in API level 9

Converts the byte array to a string using the given charset.

The behavior when the bytes cannot be decoded by the given charset is to replace malformed input and unmappable code points with the charset's default replacement string. Use CharsetDecoder for more control.

Parameters
data
offset
byteCount
charset
Throws
IndexOutOfBoundsException if byteCount < 0 || offset < 0 || offset + byteCount > data.length
NullPointerException if data == null

public String (byte[] data, Charset charset)

Added in API level 9

Converts the byte array to a String using the given charset.

Parameters
data
charset
Throws
NullPointerException if data == null

public String (char[] data)

Added in API level 1

Initializes this string to contain the given chars. Modifying the array after creating the string has no effect on the string.

Parameters
data
Throws
NullPointerException if data == null

public String (char[] data, int offset, int charCount)

Added in API level 1

Initializes this string to contain the given chars. Modifying the array after creating the string has no effect on the string.

Parameters
data
offset
charCount
Throws
NullPointerException if data == null.
IndexOutOfBoundsException if charCount < 0 || offset < 0 || offset + charCount > data.length

public String (String toCopy)

Added in API level 1

Constructs a new string with the same sequence of characters as toCopy.

Parameters
toCopy

public String (StringBuffer stringBuffer)

Added in API level 1

Creates a String from the contents of the specified StringBuffer.

Parameters
stringBuffer

public String (int[] codePoints, int offset, int count)

Added in API level 1

Creates a String from the sub-array of Unicode code points.

Parameters
codePoints
offset
count
Throws
NullPointerException if codePoints == null.
IllegalArgumentException if any of the elements of codePoints are not valid Unicode code points.
IndexOutOfBoundsException if offset or count are not within the bounds of codePoints.

public String (StringBuilder stringBuilder)

Added in API level 1

Creates a String from the contents of the specified StringBuilder.

Parameters
stringBuilder
Throws
NullPointerException if stringBuilder == null.

Public Methods

public char charAt (int index)

Added in API level 1

Returns the char at index.

Parameters
index
Returns
char
Throws
IndexOutOfBoundsException if index < 0 or index >= length().

public int codePointAt (int index)

Added in API level 1

Returns the Unicode code point at the given index.

Parameters
index
Returns
int
Throws
IndexOutOfBoundsException if index < 0 || index >= length()

public int codePointBefore (int index)

Added in API level 1

Returns the Unicode code point that precedes the given index.

Parameters
index
Returns
int
Throws
IndexOutOfBoundsException if index < 1 || index > length()

public int codePointCount (int start, int end)

Added in API level 1

Calculates the number of Unicode code points between start and end.

Parameters
start the inclusive beginning index of the subsequence.
end the exclusive end index of the subsequence.
Returns
int the number of Unicode code points in the subsequence.
Throws
IndexOutOfBoundsException if start < 0 || end > length() || start > end

public int compareTo (String string)

Added in API level 1

Compares this string to the given string.

The strings are compared one char at a time. In the discussion of the return value below, note that char does not mean code point, though this should only be visible for surrogate pairs.

If there is an index at which the two strings differ, the result is the difference between the two chars at the lowest such index. If not, but the lengths of the strings differ, the result is the difference between the two strings' lengths. If the strings are the same length and every char is the same, the result is 0.

Parameters
string
Returns
int
Throws
NullPointerException if string is null.

public int compareToIgnoreCase (String string)

Added in API level 1

Compares this string to the given string, ignoring case differences.

The strings are compared one char at a time. This is not suitable for case-insensitive string comparison for all locales. Use a Collator instead.

If there is an index at which the two strings differ, the result is the difference between the two chars at the lowest such index. If not, but the lengths of the strings differ, the result is the difference between the two strings' lengths. If the strings are the same length and every char is the same, the result is 0.

Parameters
string
Returns
int
Throws
NullPointerException if string is null.

public String concat (String string)

Added in API level 1

Concatenates this string and the specified string.

Parameters
string the string to concatenate
Returns
String a new string which is the concatenation of this string and the specified string.

public boolean contains (CharSequence cs)

Added in API level 1

Returns true if this string contains the charss from the given CharSequence.

Parameters
cs
Returns
boolean

public boolean contentEquals (CharSequence cs)

Added in API level 1

Returns true if the chars in the given CharSequence are the same as those in this string.

Parameters
cs
Returns
boolean

public boolean contentEquals (StringBuffer sb)

Added in API level 1

Returns true if the chars in the given StringBuffer are the same as those in this string.

Parameters
sb
Returns
boolean
Throws
NullPointerException if sb is null.

public static String copyValueOf (char[] data, int start, int length)

Added in API level 1

Creates a new string by copying the given subsequence of the given char[]. Modifying the array after creating the string has no effect on the string.

Parameters
data
start
length
Returns
String
Throws
NullPointerException if data is null.
IndexOutOfBoundsException if length < 0, start < 0 or start + length > data.length.

public static String copyValueOf (char[] data)

Added in API level 1

Creates a new string by copying the given char[]. Modifying the array after creating the string has no effect on the string.

Parameters
data
Returns
String
Throws
NullPointerException if data is null.

public boolean endsWith (String suffix)

Added in API level 1

Compares the specified string to this string to determine if the specified string is a suffix.

Parameters
suffix
Returns
boolean
Throws
NullPointerException if suffix is null.

public boolean equals (Object other)

Added in API level 1

Compares the given object to this string and returns true if they are equal. The object must be an instance of String with the same length, where for every index, charAt on each string returns the same value.

Parameters
other the object to compare this instance with.
Returns
boolean true if the specified object is equal to this Object; false otherwise.

public boolean equalsIgnoreCase (String string)

Added in API level 1

Compares the given string to this string ignoring case.

The strings are compared one char at a time. This is not suitable for case-insensitive string comparison for all locales. Use a Collator instead.

Parameters
string
Returns
boolean

public static String format (Locale locale, String format, Object... args)

Added in API level 1

Returns a formatted string, using the supplied format and arguments, localized to the given locale.

Parameters
locale the locale to apply; null value means no localization.
format the format string (see format(String, Object...))
args the list of arguments passed to the formatter. If there are more arguments than required by format, additional arguments are ignored.
Returns
String the formatted string.
Throws
NullPointerException if format == null
IllegalFormatException if the format is invalid.

public static String format (String format, Object... args)

Added in API level 1

Returns a localized formatted string, using the supplied format and arguments, using the user's default locale.

If you're formatting a string other than for human consumption, you should use the format(Locale, String, Object...) overload and supply Locale.US. See "Be wary of the default locale".

Parameters
format the format string (see format(String, Object...))
args the list of arguments passed to the formatter. If there are more arguments than required by format, additional arguments are ignored.
Returns
String the formatted string.
Throws
NullPointerException if format == null
IllegalFormatException if the format is invalid.

public void getBytes (int start, int end, byte[] data, int index)

Added in API level 1

This method was deprecated in API level 1.
Use getBytes() or getBytes(String)

Mangles a subsequence of this string into a byte array by stripping the high order bits from each char. Use getBytes() or getBytes(String) instead.

Parameters
start the start offset in this string.
end the end+1 offset in this string.
data the destination byte array.
index the start offset in the destination byte array.
Throws
NullPointerException if data is null.
IndexOutOfBoundsException if start < 0, end > length(), index < 0 or end - start > data.length - index.

public byte[] getBytes (String charsetName)

Added in API level 1

Returns a new byte array containing the code points of this string encoded using the named charset.

The behavior when this string cannot be represented in the named charset is unspecified. Use CharsetEncoder for more control.

Parameters
charsetName
Returns
byte[]
Throws
UnsupportedEncodingException if the charset is not supported

public byte[] getBytes (Charset charset)

Added in API level 9

Returns a new byte array containing the code points of this string encoded using the given charset.

The behavior when this string cannot be represented in the given charset is to replace malformed input and unmappable code points with the charset's default replacement byte array. Use CharsetEncoder for more control.

Parameters
charset
Returns
byte[]

public byte[] getBytes ()

Added in API level 1

Returns a new byte array containing the code points in this string encoded using the system's default charset.

The behavior when this string cannot be represented in the system's default charset is unspecified. In practice, when the default charset is UTF-8 (as it is on Android), all strings can be encoded.

Returns
byte[]

public void getChars (int start, int end, char[] buffer, int index)

Added in API level 1

Copies the given subsequence of this string to the given array starting at the given offset.

Parameters
start the start offset in this string.
end the end+1 offset in this string.
buffer the destination array.
index the start offset in the destination array.
Throws
NullPointerException if buffer is null.
IndexOutOfBoundsException if start < 0, end > length(), start > end, index < 0, end - start > buffer.length - index

public int hashCode ()

Added in API level 1

Returns an integer hash code for this object. By contract, any two objects for which equals(Object) returns true must return the same hash code value. This means that subclasses of Object usually override both methods or neither method.

Note that hash values must not change over time unless information used in equals comparisons also changes.

See Writing a correct hashCode method if you intend implementing your own hashCode method.

Returns
int this object's hash code.

public int indexOf (int c)

Added in API level 1

Returns the first index of the given code point, or -1. The search starts at the beginning and moves towards the end of this string.

Parameters
c
Returns
int

public int indexOf (int c, int start)

Added in API level 1

Returns the next index of the given code point, or -1. The search starts at the given offset and moves towards the end of this string.

Parameters
c
start
Returns
int

public int indexOf (String subString, int start)

Added in API level 1

Returns the next index of the given string in this string, or -1. The search for the string starts at the given offset and moves towards the end of this string.

Parameters
subString
start
Returns
int
Throws
NullPointerException if subString is null.

public int indexOf (String string)

Added in API level 1

Returns the first index of the given string, or -1. The search starts at the beginning and moves towards the end of this string.

Parameters
string
Returns
int
Throws
NullPointerException if string is null.

public String intern ()

Added in API level 1

Returns an interned string equal to this string. The VM maintains an internal set of unique strings. All string literals found in loaded classes' constant pools are automatically interned. Manually-interned strings are only weakly referenced, so calling intern won't lead to unwanted retention.

Interning is typically used because it guarantees that for interned strings a and b, a.equals(b) can be simplified to a == b. (This is not true of non-interned strings.)

Many applications find it simpler and more convenient to use an explicit HashMap to implement their own pools.

Returns
String

public boolean isEmpty ()

Added in API level 9

Returns true if the length of this string is 0.

Returns
boolean

public int lastIndexOf (String string)

Added in API level 1

Returns the index of the start of the last match for the given string in this string, or -1. The search for the string starts at the end and moves towards the beginning of this string.

Parameters
string
Returns
int
Throws
NullPointerException if string is null.

public int lastIndexOf (int c, int start)

Added in API level 1

Returns the last index of the code point c, or -1. The search starts at offset start and moves towards the beginning of this string.

Parameters
c
start
Returns
int

public int lastIndexOf (int c)

Added in API level 1

Returns the last index of the code point c, or -1. The search starts at the end and moves towards the beginning of this string.

Parameters
c
Returns
int

public int lastIndexOf (String subString, int start)

Added in API level 1

Returns the index of the start of the previous match for the given string in this string, or -1. The search for the string starts at the given index and moves towards the beginning of this string.

Parameters
subString
start
Returns
int
Throws
NullPointerException if subString is null.

public int length ()

Added in API level 1

Returns the number of chars in this string. If this string contains surrogate pairs, this is not the same as the number of code points.

Returns
int the number of characters.

public boolean matches (String regularExpression)

Added in API level 1

Tests whether this string matches the given regularExpression. This method returns true only if the regular expression matches the entire input string. A common mistake is to assume that this method behaves like contains(CharSequence); if you want to match anywhere within the input string, you need to add .* to the beginning and end of your regular expression. See matches(String, CharSequence).

If the same regular expression is to be used for multiple operations, it may be more efficient to reuse a compiled Pattern.

Parameters
regularExpression
Returns
boolean
Throws
if the syntax of the supplied regular expression is not valid.
NullPointerException if regularExpression == null

public int offsetByCodePoints (int index, int codePointOffset)

Added in API level 1

Returns the index within this object that is offset from index by codePointOffset code points.

Parameters
index the index within this object to calculate the offset from.
codePointOffset the number of code points to count.
Returns
int the index within this object that is the offset.
Throws
IndexOutOfBoundsException if index is negative or greater than length() or if there aren't enough code points before or after index to match codePointOffset.

public boolean regionMatches (boolean ignoreCase, int thisStart, String string, int start, int length)

Added in API level 1

Returns true if the given subsequence of the given string matches this string starting at the given offset.

If ignoreCase is true, case is ignored during the comparison. The strings are compared one char at a time. This is not suitable for case-insensitive string comparison for all locales. Use a Collator instead.

Parameters
ignoreCase specifies if case should be ignored (use Collator instead for non-ASCII case insensitivity).
thisStart the start offset in this string.
string the other string.
start the start offset in string.
length the number of chars to compare.
Returns
boolean
Throws
NullPointerException if string is null.

public boolean regionMatches (int thisStart, String string, int start, int length)

Added in API level 1

Returns true if the given subsequence of the given string matches this string starting at the given offset.

Parameters
thisStart the start offset in this string.
string the other string.
start the start offset in string.
length the number of chars to compare.
Returns
boolean
Throws
NullPointerException if string is null.

public String replace (CharSequence target, CharSequence replacement)

Added in API level 1

Returns a copy of this string after replacing occurrences of target replaced with replacement. The string is processed from the beginning to the end.

Parameters
target
replacement
Returns
String
Throws
NullPointerException if target or replacement is null.

public String replace (char oldChar, char newChar)

Added in API level 1

Returns a copy of this string after replacing occurrences of the given char with another.

Parameters
oldChar
newChar
Returns
String

public String replaceAll (String regularExpression, String replacement)

Added in API level 1

Replaces all matches for regularExpression within this string with the given replacement. See Pattern for regular expression syntax.

If the same regular expression is to be used for multiple operations, it may be more efficient to reuse a compiled Pattern.

Parameters
regularExpression
replacement
Returns
String
Throws
if the syntax of the supplied regular expression is not valid.
NullPointerException if regularExpression == null

See also:

public String replaceFirst (String regularExpression, String replacement)

Added in API level 1

Replaces the first match for regularExpression within this string with the given replacement. See Pattern for regular expression syntax.

If the same regular expression is to be used for multiple operations, it may be more efficient to reuse a compiled Pattern.

Parameters
regularExpression
replacement
Returns
String
Throws
if the syntax of the supplied regular expression is not valid.
NullPointerException if regularExpression == null

See also:

public String[] split (String regularExpression)

Added in API level 1

Splits this string using the supplied regularExpression. Equivalent to split(regularExpression, 0). See split(CharSequence, int) for an explanation of limit. See Pattern for regular expression syntax.

If the same regular expression is to be used for multiple operations, it may be more efficient to reuse a compiled Pattern.

Parameters
regularExpression
Returns
String[]
Throws
NullPointerException if regularExpression == null
if the syntax of the supplied regular expression is not valid.

See also:

public String[] split (String regularExpression, int limit)

Added in API level 1

Splits this string using the supplied regularExpression. See split(CharSequence, int) for an explanation of limit. See Pattern for regular expression syntax.

If the same regular expression is to be used for multiple operations, it may be more efficient to reuse a compiled Pattern.

Parameters
regularExpression
limit
Returns
String[]
Throws
NullPointerException if regularExpression == null
if the syntax of the supplied regular expression is not valid.

public boolean startsWith (String prefix)

Added in API level 1

Compares the specified string to this string to determine if the specified string is a prefix.

Parameters
prefix the string to look for.
Returns
boolean true if the specified string is a prefix of this string, false otherwise
Throws
NullPointerException if prefix is null.

public boolean startsWith (String prefix, int start)

Added in API level 1

Compares the specified string to this string, starting at the specified offset, to determine if the specified string is a prefix.

Parameters
prefix the string to look for.
start the starting offset.
Returns
boolean true if the specified string occurs in this string at the specified offset, false otherwise.
Throws
NullPointerException if prefix is null.

public CharSequence subSequence (int start, int end)

Added in API level 1

Equivalent to substring(int, int) but needed to implement CharSequence.

Parameters
start the start offset of the sub-sequence. It is inclusive, that is, the index of the first character that is included in the sub-sequence.
end the end offset of the sub-sequence. It is exclusive, that is, the index of the first character after those that are included in the sub-sequence
Returns
CharSequence the requested sub-sequence.
Throws
IndexOutOfBoundsException if start < 0, end < 0, start > end or end > length().

public String substring (int start)

Added in API level 1

Returns a string containing a suffix of this string starting at start. The returned string shares this string's backing array.

Parameters
start
Returns
String
Throws
IndexOutOfBoundsException if start < 0 or start > length().

public String substring (int start, int end)

Added in API level 1

Returns a string containing the given subsequence of this string. The returned string shares this string's backing array.

Parameters
start the start offset.
end the end+1 offset.
Returns
String
Throws
IndexOutOfBoundsException if start < 0, start > end or end > length().

public char[] toCharArray ()

Added in API level 1

Returns a new char array containing a copy of the chars in this string. This is expensive and rarely useful. If you just want to iterate over the chars in the string, use charAt(int) instead.

Returns
char[]

public String toLowerCase (Locale locale)

Added in API level 1

Converts this string to lower case, using the rules of locale.

Most case mappings are unaffected by the language of a Locale. Exceptions include dotted and dotless I in Azeri and Turkish locales, and dotted and dotless I and J in Lithuanian locales. On the other hand, it isn't necessary to provide a Greek locale to get correct case mapping of Greek characters: any locale will do.

See http://www.unicode.org/Public/UNIDATA/SpecialCasing.txt for full details of context- and language-specific special cases.

Parameters
locale
Returns
String a new lower case string, or this if it's already all lower case.

public String toLowerCase ()

Added in API level 1

Converts this string to lower case, using the rules of the user's default locale. See "Be wary of the default locale".

Returns
String a new lower case string, or this if it's already all lower case.

public String toString ()

Added in API level 1

Returns this string.

Returns
String a printable representation of this object.

public String toUpperCase (Locale locale)

Added in API level 1

Converts this this string to upper case, using the rules of locale.

Most case mappings are unaffected by the language of a Locale. Exceptions include dotted and dotless I in Azeri and Turkish locales, and dotted and dotless I and J in Lithuanian locales. On the other hand, it isn't necessary to provide a Greek locale to get correct case mapping of Greek characters: any locale will do.

See http://www.unicode.org/Public/UNIDATA/SpecialCasing.txt for full details of context- and language-specific special cases.

Parameters
locale
Returns
String a new upper case string, or this if it's already all upper case.

public String toUpperCase ()

Added in API level 1

Converts this this string to upper case, using the rules of the user's default locale. See "Be wary of the default locale".

Returns
String a new upper case string, or this if it's already all upper case.

public String trim ()

Added in API level 1

Returns a string with no code points <= \\u0020 at the beginning or end.

Returns
String

public static String valueOf (long value)

Added in API level 1

Returns the string representation of the given long.

Parameters
value
Returns
String

public static String valueOf (Object value)

Added in API level 1

Converts the specified object to its string representation. If the object is null return the string "null", otherwise use toString() to get the string representation.

Parameters
value the object.
Returns
String the object converted to a string, or the string "null".

public static String valueOf (char[] data)

Added in API level 1

Returns a new string containing the same chars as the given array. Modifying the array after creating the string has no effect on the string.

Parameters
data
Returns
String
Throws
NullPointerException if data is null.

public static String valueOf (double value)

Added in API level 1

Returns the string representation of the given double.

Parameters
value
Returns
String

public static String valueOf (int value)

Added in API level 1

Returns the string representation of the given int.

Parameters
value
Returns
String

public static String valueOf (float value)

Added in API level 1

Returns the string representation of the given float.

Parameters
value
Returns
String

public static String valueOf (char[] data, int start, int length)

Added in API level 1

Returns a new string containing the same chars as the given subset of the given array. Modifying the array after creating the string has no effect on the string.

Parameters
data
start
length
Returns
String
Throws
IndexOutOfBoundsException if length < 0, start < 0 or start + length > data.length
NullPointerException if data is null.

public static String valueOf (boolean value)

Added in API level 1

Converts the specified boolean to its string representation. When the boolean is true return "true", otherwise return "false".

Parameters
value the boolean.
Returns
String the boolean converted to a string.

public static String valueOf (char value)

Added in API level 1

Returns a new string of just the given char.

Parameters
value
Returns
String