URLDecoder

public class URLDecoder
extends Object

java.lang.Object
↳	java.net.URLDecoder

Utility class for HTML form decoding. This class contains static methods for decoding a String from the application/x-www-form-urlencoded MIME format.

The conversion process is the reverse of that used by the URLEncoder class. It is assumed that all characters in the encoded string are one of the following: "a" through "z", "A" through "Z", "0" through "9", and "-", "_", ".", and "*". The character "%" is allowed but is interpreted as the start of a special escaped sequence.

The following rules are applied in the conversion:

The alphanumeric characters "a" through "z", "A" through "Z" and "0" through "9" remain the same.
The special characters ".", "-", "*", and "_" remain the same.
The plus sign "+" is converted into a space character " " .
A sequence of the form "%xy" will be treated as representing a byte where xy is the two-digit hexadecimal representation of the 8 bits. Then, all substrings that contain one or more of these byte sequences consecutively will be replaced by the character(s) whose encoding would result in those consecutive bytes. The encoding scheme used to decode these characters may be specified, or if unspecified, the default encoding of the platform will be used.

There are two possible ways in which this decoder could deal with illegal strings. It could either leave illegal characters alone or it could throw an IllegalArgumentException. Which approach the decoder takes is left to the implementation.

Summary

Public constructors
`URLDecoder()`

Public methods
`static String`	`decode(String s)` This method was deprecated in API level 15. The resulting string may vary depending on the platform's default encoding. Instead, use the decode(String,String) method to specify the encoding.
`static String`	`decode(String s, Charset charset)` Decodes an `application/x-www-form-urlencoded` string using a specific Charset.
`static String`	`decode(String s, String enc)` Decodes an `application/x-www-form-urlencoded` string using a specific encoding scheme.

Inherited methods

From class


        
          java.lang.Object

`Object`	`clone()` Creates and returns a copy of this object.
`boolean`	`equals(Object obj)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `Object`.
`int`	`hashCode()` Returns a hash code value for the object.
`final void`	`notify()` Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()` Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()` Returns a string representation of the object.
`final void`	`wait(long timeoutMillis, int nanos)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait()` Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public constructors

URLDecoder

Added in API level 1

public URLDecoder ()

Public methods

decode

Added in API level 1
Deprecated in API level 15

public static String decode (String s)

This method was deprecated in API level 15.
The resulting string may vary depending on the platform's default encoding. Instead, use the decode(String,String) method to specify the encoding.

Decodes a x-www-form-urlencoded string. The platform's default encoding is used to determine what characters are represented by any consecutive sequences of the form "%xy".

Parameters
`s`	`String`: the `String` to decode

Returns
`String`	the newly decoded `String`

decode

Added in API level 33

public static String decode (String s, 
                Charset charset)

Decodes an application/x-www-form-urlencoded string using a specific Charset. The supplied charset is used to determine what characters are represented by any consecutive sequences of the form "%xy".

Note: The World Wide Web Consortium Recommendation states that UTF-8 should be used. Not doing so may introduce incompatibilities.

Implementation Note:

This implementation will throw an IllegalArgumentException when illegal strings are encountered.

Parameters
`s`	`String`: the `String` to decode
`charset`	`Charset`: the given charset

Returns
`String`	the newly decoded `String`

Throws
`NullPointerException`	if `s` or `charset` is `null`
`IllegalArgumentException`	if the implementation encounters illegal characters

See also:

URLEncoder.encode(java.lang.String, java.nio.charset.Charset)

decode

Added in API level 1

public static String decode (String s, 
                String enc)

Decodes an application/x-www-form-urlencoded string using a specific encoding scheme.

This method behaves the same as decode(String s, Charset charset) except that it will look up the charset using the given encoding name.

Implementation Note:

This implementation will throw an IllegalArgumentException when illegal strings are encountered.

Parameters
`s`	`String`: the `String` to decode
`enc`	`String`: The name of a supported character encoding.

Returns
`String`	the newly decoded `String`

Throws
`UnsupportedEncodingException`	If character encoding needs to be consulted, but named character encoding is not supported

See also:

URLEncoder.encode(java.lang.String, java.lang.String)