Class QueryStringDecoder

java.lang.Object
io.netty.handler.codec.http.QueryStringDecoder
public class QueryStringDecoder extends java.lang.Object
Splits an HTTP query string into a path string and key-value parameter pairs. This decoder is for one time use only. Create a new instance for each URI: 
QueryStringDecoder decoder = new QueryStringDecoder("/hello?recipient=worldinvalid input: '&x'=1;y=2");
assert decoder.path().equals("/hello");
assert decoder.parameters().get("recipient").get(0).equals("world");
assert decoder.parameters().get("x").get(0).equals("1");
assert decoder.parameters().get("y").get(0).equals("2");
This decoder can also decode the content of an HTTP POST request whose content type is application/x-www-form-urlencoded: 
QueryStringDecoder decoder = new QueryStringDecoder("recipient=worldinvalid input: '&x'=1;y=2", false);
...

HashDOS vulnerability fix

As a workaround to the HashDOS vulnerability, the decoder limits the maximum number of decoded key-value parameter pairs, up to 1024 by default, and you can configure it when you construct the decoder by passing an additional integer parameter.
See Also:

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static final class 
    QueryStringDecoder.Builder
     

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final java.nio.charset.Charset
    charset
     
    private static final int
    DEFAULT_MAX_PARAMS
     
    private final boolean
    htmlQueryDecoding
     
    private final int
    maxParams
     
    private java.util.Map<java.lang.String, java.util.List<java.lang.String>>
    params
     
    private java.lang.String
    path
     
    private int
    pathEndIdx
     
    private final boolean
    semicolonIsNormalChar
     
    private final java.lang.String
    uri
     

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    QueryStringDecoder(QueryStringDecoder.Builder builder, java.lang.String uri)
     
    private
    QueryStringDecoder(QueryStringDecoder.Builder builder, java.net.URI uri)
     
     
    QueryStringDecoder(java.lang.String uri)
    Creates a new decoder that decodes the specified URI.
     
    QueryStringDecoder(java.lang.String uri, boolean hasPath)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.
     
    QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.
     
    QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset, boolean hasPath)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.
     
    QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset, boolean hasPath, int maxParams)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.
     
    QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset, boolean hasPath, int maxParams, boolean semicolonIsNormalChar)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.
     
    QueryStringDecoder(java.net.URI uri)
    Creates a new decoder that decodes the specified URI.
     
    QueryStringDecoder(java.net.URI uri, java.nio.charset.Charset charset)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.
     
    QueryStringDecoder(java.net.URI uri, java.nio.charset.Charset charset, int maxParams)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.
     
    QueryStringDecoder(java.net.URI uri, java.nio.charset.Charset charset, int maxParams, boolean semicolonIsNormalChar)
    Creates a new decoder that decodes the specified URI encoded in the specified charset.

  • Method Summary

    Modifier and Type
    Method
    Description
    private boolean
    addParam(java.lang.String s, int nameStart, int valueStart, int valueEnd, java.util.Map<java.lang.String, java.util.List<java.lang.String>> params, java.nio.charset.Charset charset)
     
    static QueryStringDecoder.Builder
    builder()
     
    static java.lang.String
    decodeComponent(java.lang.String s)
    Decodes a bit of a URL encoded by a browser.
    private static java.lang.String
    decodeComponent(java.lang.String s, int from, int toExcluded, java.nio.charset.Charset charset, boolean plusToSpace)
     
    static java.lang.String
    decodeComponent(java.lang.String s, java.nio.charset.Charset charset)
    Decodes a bit of a URL encoded by a browser.
    private java.util.Map<java.lang.String, java.util.List<java.lang.String>>
    decodeParams(java.lang.String s, int from, java.nio.charset.Charset charset, int paramsLimit)
     
    private static int
    findPathEndIndex(java.lang.String uri)
     
    java.util.Map<java.lang.String, java.util.List<java.lang.String>>
    parameters()
    Returns the decoded key-value parameter pairs of the URI.
    java.lang.String
    path()
    Returns the decoded path string of the URI.
    private int
    pathEndIdx()
     
    java.lang.String
    rawPath()
    Returns the raw path string of the URI.
    java.lang.String
    rawQuery()
    Returns raw query string of the URI.
    java.lang.String
    toString()
     
    java.lang.String
    uri()
    Returns the uri used to initialize this QueryStringDecoder.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Field Details

    • DEFAULT_MAX_PARAMS

      private static final int DEFAULT_MAX_PARAMS
      See Also:

    • charset

      private final java.nio.charset.Charset charset

    • uri

      private final java.lang.String uri

    • maxParams

      private final int maxParams

    • semicolonIsNormalChar

      private final boolean semicolonIsNormalChar

    • htmlQueryDecoding

      private final boolean htmlQueryDecoding

    • pathEndIdx

      private int pathEndIdx

    • path

      private java.lang.String path

    • params

      private java.util.Map<java.lang.String, java.util.List<java.lang.String>> params

  • Constructor Details

    • QueryStringDecoder

      public QueryStringDecoder(java.lang.String uri)
      Creates a new decoder that decodes the specified URI. The decoder will assume that the query string is encoded in UTF-8.

    • QueryStringDecoder

      public QueryStringDecoder(java.lang.String uri, boolean hasPath)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      public QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      public QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset, boolean hasPath)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      public QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset, boolean hasPath, int maxParams)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      public QueryStringDecoder(java.lang.String uri, java.nio.charset.Charset charset, boolean hasPath, int maxParams, boolean semicolonIsNormalChar)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      public QueryStringDecoder(java.net.URI uri)
      Creates a new decoder that decodes the specified URI. The decoder will assume that the query string is encoded in UTF-8.

    • QueryStringDecoder

      public QueryStringDecoder(java.net.URI uri, java.nio.charset.Charset charset)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      public QueryStringDecoder(java.net.URI uri, java.nio.charset.Charset charset, int maxParams)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      public QueryStringDecoder(java.net.URI uri, java.nio.charset.Charset charset, int maxParams, boolean semicolonIsNormalChar)
      Creates a new decoder that decodes the specified URI encoded in the specified charset.

    • QueryStringDecoder

      private QueryStringDecoder(QueryStringDecoder.Builder builder, java.lang.String uri)

    • QueryStringDecoder

      private QueryStringDecoder(QueryStringDecoder.Builder builder, java.net.URI uri)

  • Method Details

    • toString

      public java.lang.String toString()
      Overrides:
      toString in class java.lang.Object

    • uri

      public java.lang.String uri()
      Returns the uri used to initialize this QueryStringDecoder.

    • path

      public java.lang.String path()
      Returns the decoded path string of the URI.

    • parameters

      public java.util.Map<java.lang.String, java.util.List<java.lang.String>> parameters()
      Returns the decoded key-value parameter pairs of the URI.

    • rawPath

      public java.lang.String rawPath()
      Returns the raw path string of the URI.

    • rawQuery

      public java.lang.String rawQuery()
      Returns raw query string of the URI.

    • pathEndIdx

      private int pathEndIdx()

    • decodeParams

      private java.util.Map<java.lang.String, java.util.List<java.lang.String>> decodeParams(java.lang.String s, int from, java.nio.charset.Charset charset, int paramsLimit)

    • addParam

      private boolean addParam(java.lang.String s, int nameStart, int valueStart, int valueEnd, java.util.Map<java.lang.String, java.util.List<java.lang.String>> params, java.nio.charset.Charset charset)

    • decodeComponent

      public static java.lang.String decodeComponent(java.lang.String s)
      Decodes a bit of a URL encoded by a browser.

      This is equivalent to calling decodeComponent(String, Charset) with the UTF-8 charset (recommended to comply with RFC 3986, Section 2).

      Parameters:
      s - The string to decode (can be empty).
      Returns:
      The decoded string, or s if there's nothing to decode. If the string to decode is null, returns an empty string.
      Throws:
      java.lang.IllegalArgumentException - if the string contains a malformed escape sequence.

    • decodeComponent

      public static java.lang.String decodeComponent(java.lang.String s, java.nio.charset.Charset charset)
      Decodes a bit of a URL encoded by a browser.

      The string is expected to be encoded as per RFC 3986, Section 2. This is the encoding used by JavaScript functions encodeURI and encodeURIComponent, but not escape. For example in this encoding, é (in Unicode U+00E9 or in UTF-8 0xC3 0xA9) is encoded as %C3%A9 or %c3%a9.

      This is essentially equivalent to calling URLDecoder.decode(String, String) except that it's over 2x faster and generates less garbage for the GC. Actually this function doesn't allocate any memory if there's nothing to decode, the argument itself is returned.

      Parameters:
      s - The string to decode (can be empty).
      charset - The charset to use to decode the string (should really be CharsetUtil.UTF_8.
      Returns:
      The decoded string, or s if there's nothing to decode. If the string to decode is null, returns an empty string.
      Throws:
      java.lang.IllegalArgumentException - if the string contains a malformed escape sequence.

    • decodeComponent

      private static java.lang.String decodeComponent(java.lang.String s, int from, int toExcluded, java.nio.charset.Charset charset, boolean plusToSpace)

    • findPathEndIndex

      private static int findPathEndIndex(java.lang.String uri)

    • builder

      public static QueryStringDecoder.Builder builder()