org.apache.commons.codec.binary

Class StringUtils

java.lang.Object

org.apache.commons.codec.binary.StringUtils

public class StringUtils
extends java.lang.Object

Converts String to and from bytes using the encodings required by the Java specification. These encodings are specified in Standard charsets.

This class is immutable and thread-safe.

Since:

1.4

See Also:

CharEncoding, Standard charsets

Constructor Summary

Constructors

Constructor and Description
StringUtils()

Method Summary

Modifier and Type	Method and Description
static boolean	equals(java.lang.CharSequence cs1, java.lang.CharSequence cs2) Compares two CharSequences, returning true if they represent equal sequences of characters.
static java.nio.ByteBuffer	getByteBufferUtf8(java.lang.String string) Encodes the given string into a byte buffer using the UTF-8 charset, storing the result into a new byte array.
static byte[]	getBytesIso8859_1(java.lang.String string) Encodes the given string into a sequence of bytes using the ISO-8859-1 charset, storing the result into a new byte array.
static byte[]	getBytesUnchecked(java.lang.String string, java.lang.String charsetName) Encodes the given string into a sequence of bytes using the named charset, storing the result into a new byte array.
static byte[]	getBytesUsAscii(java.lang.String string) Encodes the given string into a sequence of bytes using the US-ASCII charset, storing the result into a new byte array.
static byte[]	getBytesUtf16(java.lang.String string) Encodes the given string into a sequence of bytes using the UTF-16 charset, storing the result into a new byte array.
static byte[]	getBytesUtf16Be(java.lang.String string) Encodes the given string into a sequence of bytes using the UTF-16BE charset, storing the result into a new byte array.
static byte[]	getBytesUtf16Le(java.lang.String string) Encodes the given string into a sequence of bytes using the UTF-16LE charset, storing the result into a new byte array.
static byte[]	getBytesUtf8(java.lang.String string) Encodes the given string into a sequence of bytes using the UTF-8 charset, storing the result into a new byte array.
static java.lang.String	newString(byte[] bytes, java.lang.String charsetName) Constructs a new String by decoding the specified array of bytes using the given charset.
static java.lang.String	newStringIso8859_1(byte[] bytes) Constructs a new String by decoding the specified array of bytes using the ISO-8859-1 charset.
static java.lang.String	newStringUsAscii(byte[] bytes) Constructs a new String by decoding the specified array of bytes using the US-ASCII charset.
static java.lang.String	newStringUtf16(byte[] bytes) Constructs a new String by decoding the specified array of bytes using the UTF-16 charset.
static java.lang.String	newStringUtf16Be(byte[] bytes) Constructs a new String by decoding the specified array of bytes using the UTF-16BE charset.
static java.lang.String	newStringUtf16Le(byte[] bytes) Constructs a new String by decoding the specified array of bytes using the UTF-16LE charset.
static java.lang.String	newStringUtf8(byte[] bytes) Constructs a new String by decoding the specified array of bytes using the UTF-8 charset.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StringUtils

public StringUtils()

Method Detail

equals

public static boolean equals(java.lang.CharSequence cs1,
                             java.lang.CharSequence cs2)

Compares two CharSequences, returning true if they represent equal sequences of characters.

nulls are handled without exceptions. Two null references are considered to be equal. The comparison is case sensitive.

 StringUtils.equals(null, null)   = true
 StringUtils.equals(null, "abc")  = false
 StringUtils.equals("abc", null)  = false
 StringUtils.equals("abc", "abc") = true
 StringUtils.equals("abc", "ABC") = false
 

Copied from Apache Commons Lang r1583482 on April 10, 2014 (day of 3.3.2 release).

Parameters:

cs1 - the first CharSequence, may be null

cs2 - the second CharSequence, may be null

Returns:

true if the CharSequences are equal (case-sensitive), or both null

Since:

1.10

See Also:

Object.equals(Object)

getByteBufferUtf8

public static java.nio.ByteBuffer getByteBufferUtf8(java.lang.String string)

Encodes the given string into a byte buffer using the UTF-8 charset, storing the result into a new byte array.

Parameters:

string - the String to encode, may be null

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_8 is not initialized, which should never happen since it is required by the Java platform specification.

Since:

1.11

See Also:

Standard charsets, getBytesUnchecked(String, String)

getBytesIso8859_1

public static byte[] getBytesIso8859_1(java.lang.String string)

Encodes the given string into a sequence of bytes using the ISO-8859-1 charset, storing the result into a new byte array.

Parameters:

string - the String to encode, may be null

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.ISO_8859_1 is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

See Also:

Standard charsets, getBytesUnchecked(String, String)

getBytesUnchecked

public static byte[] getBytesUnchecked(java.lang.String string,
                                       java.lang.String charsetName)

Encodes the given string into a sequence of bytes using the named charset, storing the result into a new byte array.

This method catches UnsupportedEncodingException and rethrows it as IllegalStateException, which should never happen for a required charset name. Use this method when the encoding is required to be in the JRE.

Parameters:

string - the String to encode, may be null

charsetName - The name of a required Charset

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.IllegalStateException - Thrown when a UnsupportedEncodingException is caught, which should never happen for a required charset name.

See Also:

CharEncoding, String.getBytes(String)

getBytesUsAscii

public static byte[] getBytesUsAscii(java.lang.String string)

Encodes the given string into a sequence of bytes using the US-ASCII charset, storing the result into a new byte array.

Parameters:

string - the String to encode, may be null

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.US_ASCII is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

See Also:

Standard charsets, getBytesUnchecked(String, String)

getBytesUtf16

public static byte[] getBytesUtf16(java.lang.String string)

Encodes the given string into a sequence of bytes using the UTF-16 charset, storing the result into a new byte array.

Parameters:

string - the String to encode, may be null

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_16 is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

See Also:

Standard charsets, getBytesUnchecked(String, String)

getBytesUtf16Be

public static byte[] getBytesUtf16Be(java.lang.String string)

Encodes the given string into a sequence of bytes using the UTF-16BE charset, storing the result into a new byte array.

Parameters:

string - the String to encode, may be null

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_16BE is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

See Also:

Standard charsets, getBytesUnchecked(String, String)

getBytesUtf16Le

public static byte[] getBytesUtf16Le(java.lang.String string)

Encodes the given string into a sequence of bytes using the UTF-16LE charset, storing the result into a new byte array.

Parameters:

string - the String to encode, may be null

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_16LE is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

See Also:

Standard charsets, getBytesUnchecked(String, String)

getBytesUtf8

public static byte[] getBytesUtf8(java.lang.String string)

Encodes the given string into a sequence of bytes using the UTF-8 charset, storing the result into a new byte array.

Parameters:

string - the String to encode, may be null

Returns:

encoded bytes, or null if the input string was null

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_8 is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

See Also:

Standard charsets, getBytesUnchecked(String, String)

newString

public static java.lang.String newString(byte[] bytes,
                                         java.lang.String charsetName)

Constructs a new String by decoding the specified array of bytes using the given charset.

This method catches UnsupportedEncodingException and re-throws it as IllegalStateException, which should never happen for a required charset name. Use this method when the encoding is required to be in the JRE.

Parameters:

bytes - The bytes to be decoded into characters, may be null

charsetName - The name of a required Charset

Returns:

A new String decoded from the specified array of bytes using the given charset, or null if the input byte array was null.

Throws:

java.lang.IllegalStateException - Thrown when a UnsupportedEncodingException is caught, which should never happen for a required charset name.

See Also:

CharEncoding, String.String(byte[], String)

newStringIso8859_1

public static java.lang.String newStringIso8859_1(byte[] bytes)

Constructs a new String by decoding the specified array of bytes using the ISO-8859-1 charset.

Parameters:

bytes - The bytes to be decoded into characters, may be null

Returns:

A new String decoded from the specified array of bytes using the ISO-8859-1 charset, or null if the input byte array was null.

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.ISO_8859_1 is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

newStringUsAscii

public static java.lang.String newStringUsAscii(byte[] bytes)

Constructs a new String by decoding the specified array of bytes using the US-ASCII charset.

Parameters:

bytes - The bytes to be decoded into characters

Returns:

A new String decoded from the specified array of bytes using the US-ASCII charset, or null if the input byte array was null.

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.US_ASCII is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

newStringUtf16

public static java.lang.String newStringUtf16(byte[] bytes)

Constructs a new String by decoding the specified array of bytes using the UTF-16 charset.

Parameters:

bytes - The bytes to be decoded into characters

Returns:

A new String decoded from the specified array of bytes using the UTF-16 charset or null if the input byte array was null.

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_16 is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

newStringUtf16Be

public static java.lang.String newStringUtf16Be(byte[] bytes)

Constructs a new String by decoding the specified array of bytes using the UTF-16BE charset.

Parameters:

bytes - The bytes to be decoded into characters

Returns:

A new String decoded from the specified array of bytes using the UTF-16BE charset, or null if the input byte array was null.

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_16BE is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

newStringUtf16Le

public static java.lang.String newStringUtf16Le(byte[] bytes)

Constructs a new String by decoding the specified array of bytes using the UTF-16LE charset.

Parameters:

bytes - The bytes to be decoded into characters

Returns:

A new String decoded from the specified array of bytes using the UTF-16LE charset, or null if the input byte array was null.

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_16LE is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException

newStringUtf8

public static java.lang.String newStringUtf8(byte[] bytes)

Constructs a new String by decoding the specified array of bytes using the UTF-8 charset.

Parameters:

bytes - The bytes to be decoded into characters

Returns:

A new String decoded from the specified array of bytes using the UTF-8 charset, or null if the input byte array was null.

Throws:

java.lang.NullPointerException - Thrown if StandardCharsets.UTF_8 is not initialized, which should never happen since it is required by the Java platform specification.

Since:

As of 1.7, throws NullPointerException instead of UnsupportedEncodingException