Class ContentTypeParser

java.lang.Object
org.simpleframework.common.parse.Parser
org.simpleframework.http.parse.ContentTypeParser
All Implemented Interfaces:
ContentType
public class ContentTypeParser extends Parser implements ContentType
This provides access to the MIME type parts, that is the primary type, the secondary type and an optional character set parameter. The charset parameter is one of many parameters that can be associated with a MIME type. This however this exposes this parameter with a typed method.

The getCharset will return the character encoding the content type is encoded within. This allows the user of the content to decode it correctly. Other parameters can be acquired from this by simply providing the name of the parameter.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private ParseBuffer
    charset
    Used to store the characters for the charset parameter.
    private KeyMap<String>
    map
    Used to store the name value pairs of the parameters.
    private ParseBuffer
    name
    Used to collect the name of a content type parameter.
    private ParseBuffer
    primary
    Used to store the characters consumed for the primary type.
    private ParseBuffer
    secondary
    Used to store the characters consumed for the secondary type.
    private ParseBuffer
    type
    Used to store the characters consumed for the type.
    private ParseBuffer
    value
    Used to collect the value of the content type parameter.

    Fields inherited from class Parser

    buf, count, off

  • Constructor Summary

    Constructors
    Constructor
    Description
    ContentTypeParser()
    The default constructor will create a ContentParser that contains no charset, primary or secondary.
    ContentTypeParser(String header)
    This is primarily a convenience constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    private void
    charset()
    This is used to read the value from the charset param.
    private void
    clear()
    This is used to clear all previously collected tokens.
    private String
    encode()
    This will return the value of the MIME type as a string.
    private String
    encode(StringBuilder text)
    This will return the value of the MIME type as a string.
    String
    getCharset()
    This is used to retrieve the charset of this MIME type.
    String
    getParameter(String name)
    This is used to retrieve an arbitrary parameter from the MIME type header.
    String
    getPrimary()
    This is used to retrieve the primary type of this MIME type.
    String
    getSecondary()
    This is used to retrieve the secondary type of this MIME type.
    String
    getType()
    This method is used to get the primary and secondary parts joined together with a "/".
    protected void
    init()
    This will initialize the parser when it is ready to parse a new String.
    private void
    insert()
    This will add the name and value tokens to the parameters map.
    private void
    insert(ParseBuffer name, ParseBuffer value)
    This will add the given name and value to the parameters map.
    private void
    name()
    This will simply read all characters from the buffer before the first '=' character.
    private void
    pack()
    This is used to remove all whitespace characters from the String excluding the whitespace within literals.
    private void
    parameter()
    This is a parameter as defined by RFC 2616.
    private void
    parameters()
    This will read the parameters from the MIME type.
    protected void
    parse()
    Reads and parses the MIME type from the given String object.
    private void
    primary()
    This reads the type from the MIME type.
    private boolean
    quote(char ch)
    This method is used to determine if the specified character is a quote character.
    private void
    secondary()
    This reads the subtype from the MIME type.
    void
    setCharset(String enc)
    This will set the charset to whatever value the string contains.
    void
    setParameter(String name, String value)
    This will add a named parameter to the content type header.
    void
    setPrimary(String value)
    This sets the primary type to whatever value is in the string provided is.
    void
    setSecondary(String value)
    This sets the secondary type to whatever value is in the string provided is.
    String
    toString()
    This will return the value of the MIME type as a string.
    private void
    value()
    This is used to read a parameters value from the buf.

    Methods inherited from class Parser

    digit, ensureCapacity, parse, skip, space, toLower

    Methods inherited from class Object

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

  • Field Details

    • secondary

      private ParseBuffer secondary
      Used to store the characters consumed for the secondary type.

    • primary

      private ParseBuffer primary
      Used to store the characters consumed for the primary type.

    • charset

      private ParseBuffer charset
      Used to store the characters for the charset parameter.

    • type

      private ParseBuffer type
      Used to store the characters consumed for the type.

    • name

      private ParseBuffer name
      Used to collect the name of a content type parameter.

    • value

      private ParseBuffer value
      Used to collect the value of the content type parameter.

    • map

      private KeyMap<String> map
      Used to store the name value pairs of the parameters.

  • Constructor Details

    • ContentTypeParser

      public ContentTypeParser()
      The default constructor will create a ContentParser that contains no charset, primary or secondary. This can be used to extract the primary, secondary and the optional charset parameter by using the parser's parse(String) method.

    • ContentTypeParser

      public ContentTypeParser(String header)
      This is primarily a convenience constructor. This will parse the String given to extract the MIME type. This could be achieved by calling the default no-arg constructor and then using the instance to invoke the parse method on that String.
      Parameters:
      header - String containing a MIME type value

  • Method Details

    • getType

      public String getType()
      This method is used to get the primary and secondary parts joined together with a "/". This is typically how a content type is examined. Here convenience is most important, we can easily compare content types without any parameters.
      Specified by:
      getType in interface ContentType
      Returns:
      this returns the primary and secondary types

    • setPrimary

      public void setPrimary(String value)
      This sets the primary type to whatever value is in the string provided is. If the string is null then this will contain a null string for the primary type of the parameter, which is likely invalid in most cases.
      Specified by:
      setPrimary in interface ContentType
      Parameters:
      value - the type to set for the primary type of this

    • getPrimary

      public String getPrimary()
      This is used to retrieve the primary type of this MIME type. The primary type part within the MIME type defines the generic type. For example text/plain; charset=UTF-8. This will return the text value. If there is no primary type then this will return null otherwise the string value.
      Specified by:
      getPrimary in interface ContentType
      Returns:
      the primary type part of this MIME type

    • setSecondary

      public void setSecondary(String value)
      This sets the secondary type to whatever value is in the string provided is. If the string is null then this will contain a null string for the secondary type of the parameter, which is likely invalid in most cases.
      Specified by:
      setSecondary in interface ContentType
      Parameters:
      value - the type to set for the primary type of this

    • getSecondary

      public String getSecondary()
      This is used to retrieve the secondary type of this MIME type. The secondary type part within the MIME type defines the generic type. For example text/html; charset=UTF-8. This will return the HTML value. If there is no secondary type then this will return null otherwise the string value.
      Specified by:
      getSecondary in interface ContentType
      Returns:
      the primary type part of this MIME type

    • setCharset

      public void setCharset(String enc)
      This will set the charset to whatever value the string contains. If the string is null then this will not set the parameter to any value and the toString method will not contain any details of the parameter.
      Specified by:
      setCharset in interface ContentType
      Parameters:
      enc - parameter value to add to the MIME type

    • getCharset

      public String getCharset()
      This is used to retrieve the charset of this MIME type. This is a special parameter associated with the type, if the parameter is not contained within the type then this will return null, which typically means the default of ISO-8859-1.
      Specified by:
      getCharset in interface ContentType
      Returns:
      the value that this parameter contains

    • getParameter

      public String getParameter(String name)
      This is used to retrieve an arbitrary parameter from the MIME type header. This ensures that values for boundary or other such parameters are not lost when the header is parsed. This will return the value, unquoted if required, as a string.
      Specified by:
      getParameter in interface ContentType
      Parameters:
      name - this is the name of the parameter to be retrieved
      Returns:
      this is the value for the parameter, or null if empty

    • setParameter

      public void setParameter(String name, String value)
      This will add a named parameter to the content type header. If a parameter of the specified name has already been added to the header then that value will be replaced by the new value given. Parameters such as the boundary as well as other common parameters can be set with this method.
      Specified by:
      setParameter in interface ContentType
      Parameters:
      name - this is the name of the parameter to be added
      value - this is the value to associate with the name

    • init

      protected void init()
      This will initialize the parser when it is ready to parse a new String. This will reset the parser to a ready state. The init method is invoked by the parser when the Parser.parse method is invoked.
      Specified by:
      init in class Parser

    • clear

      private void clear()
      This is used to clear all previously collected tokens. This allows the parser to be reused when there are multiple source strings to be parsed. Clearing of the tokens is performed when the parser is initialized.

    • parse

      protected void parse()
      Reads and parses the MIME type from the given String object. This uses the syntax defined by RFC 2616 for the media-type syntax. This parser is only concerned with one parameter, the charset parameter. The syntax for the media type is 
      media-type = token "/" token *( ";" parameter )
parameter = token | literal
      Specified by:
      parse in class Parser

    • pack

      private void pack()
      This is used to remove all whitespace characters from the String excluding the whitespace within literals. The definition of a literal can be found in RFC 2616.

      The definition of a literal for RFC 2616 is anything between 2 quotes but excluding quotes that are prefixed with the backward slash character.

    • primary

      private void primary()
      This reads the type from the MIME type. This will fill the type ParseBuffer. This will read all chars upto but not including the first instance of a '/'. The type of a media-type as defined by RFC 2616 is type/subtype;param=val;param2=val.

    • secondary

      private void secondary()
      This reads the subtype from the MIME type. This will fill the subtype ParseBuffer. This will read all chars upto but not including the first instance of a ';'. The subtype of a media-type as defined by RFC 2616 is type/subtype;param=val;param2=val.

    • parameters

      private void parameters()
      This will read the parameters from the MIME type. This will search for the charset parameter within the set of parameters which are given to the type. The charset param is the only parameter that this parser will tokenize.

      This will remove any parameters that preceed the charset parameter. Once the charset is retrived the MIME type is considered to be parsed.

    • insert

      private void insert()
      This will add the name and value tokens to the parameters map. If any previous value of the given name has been inserted into the map then this will overwrite that value. This is used to ensure that the string value is inserted to the map.

    • insert

      private void insert(ParseBuffer name, ParseBuffer value)
      This will add the given name and value to the parameters map. If any previous value of the given name has been inserted into the map then this will overwrite that value. This is used to ensure that the string value is inserted to the map.
      Parameters:
      name - this is the name of the value to be inserted
      value - this is the value of a that is to be inserted

    • parameter

      private void parameter()
      This is a parameter as defined by RFC 2616. The parameter is added to a MIME type e.g. type/subtype;param=val etc. The parameter name and value are not stored. This is used to simply update the read offset past the parameter. The reason for reading the parameters is to search for the charset parameter which will indicate the encoding.

    • name

      private void name()
      This will simply read all characters from the buffer before the first '=' character. This represents a parameter name (see RFC 2616 for token). The parameter name is not buffered it is simply read from the buffer. This will not cause an IndexOutOfBoundsException as each offset is checked before it is acccessed.

    • value

      private void value()
      This is used to read a parameters value from the buf. This will read all char's upto but excluding the first terminal char encountered from the off within the buf, or if the value is a literal it will read a literal from the buffer (literal is any data between quotes except if the quote is prefixed with a backward slash character).

    • quote

      private boolean quote(char ch)
      This method is used to determine if the specified character is a quote character. The quote character is typically used as a boundary for the values within the header. This accepts a single or double quote.
      Parameters:
      ch - the character to determine if it is a quotation
      Returns:
      true if the character provided is a quotation character

    • charset

      private void charset()
      This is used to read the value from the charset param. This will fill the charset ParseBuffer and with the charset value. This will read a literal or a token as the charset value. If the charset is a literal then the quotes will be read as part of the charset.

    • encode

      private String encode()
      This will return the value of the MIME type as a string. This will concatenate the primary and secondary type values and add the charset parameter to the type which will recreate the content type.
      Returns:
      this returns the string representation of the type

    • encode

      private String encode(StringBuilder text)
      This will return the value of the MIME type as a string. This will concatenate the primary and secondary type values and add the charset parameter to the type which will recreate the content type.
      Parameters:
      text - this is the buffer to encode the parameters to
      Returns:
      this returns the string representation of the type

    • toString

      public String toString()
      This will return the value of the MIME type as a string. This will concatenate the primary and secondary type values and add the charset parameter to the type which will recreate the content type.
      Specified by:
      toString in interface ContentType
      Overrides:
      toString in class Object
      Returns:
      this returns the string representation of the type