Class ManifestElement


  • public class ManifestElement
    extends Object
    This class represents a single manifest element. A manifest element must consist of a single String value. The String value may be split up into component values each separated by a semi-colon (';'). A manifest element may optionally have a set of attribute and directive values associated with it. The general syntax of a manifest element is as follows:
     ManifestElement ::= component (';' component)* (';' parameter)*
     component ::= ([^;,:="\#x0D#x0A#x00])+ | quoted-string
     quoted-string::= '"' ( [^"\#x0D#x0A#x00] | '\"'| '\\')* '"'
     parameter ::= directive | attribute 
     directive ::= token ':=' argument
     attribute ::= token '=' argument
     argument ::= extended  | quoted-string
     token ::= ( alphanum | '_' | '-' )+ 
     extended ::= ( alphanum | '_' | '-' | '.' )+ 
     

    For example, the following is an example of a manifest element to the Export-Package header:

     org.osgi.framework; specification-version="1.2"; another-attr="examplevalue"
     

    This manifest element has a value of org.osgi.framework and it has two attributes, specification-version and another-attr.

    The following manifest element is an example of a manifest element that has multiple components to its value:

     code1.jar;code2.jar;code3.jar;attr1=value1;attr2=value2;attr3=value3
     

    This manifest element has a value of code1.jar;code2.jar;code3.jar. This is an example of a multiple component value. This value has three components: code1.jar, code2.jar, and code3.jar.

    If components contain delimiter characters (e.g ';', ',' ':' "=") then it must be a quoted string. For example, the following is an example of a manifest element that has multiple components containing delimiter characters:

     "component ; 1"; "component , 2"; "component : 3"; attr1=value1; attr2=value2; attr3=value3
     

    This manifest element has a value of "component ; 1"; "component , 2"; "component : 3". This value has three components: "component ; 1", "component , 2", "component : 3".

    This class is not intended to be subclassed by clients.

    Since:
    3.0
    Restriction:
    This class is not intended to be subclassed by clients.
    • Method Detail

      • getValue

        public String getValue()
        Returns the value of the manifest element. The value returned is the complete value up to the first attribute or directive. For example, the following manifest element:
         test1.jar;test2.jar;test3.jar;selection-filter="(os.name=Windows XP)"
         

        This manifest element has a value of test1.jar;test2.jar;test3.jar

        Returns:
        the value of the manifest element.
      • getValueComponents

        public String[] getValueComponents()
        Returns the value components of the manifest element. The value components returned are the complete list of value components up to the first attribute or directive. For example, the following manifest element:
         test1.jar;test2.jar;test3.jar;selection-filter="(os.name=Windows XP)"
         

        This manifest element has the value components array { "test1.jar", "test2.jar", "test3.jar" } Each value component is delemited by a semi-colon (';').

        Returns:
        the String[] of value components
      • getAttribute

        public String getAttribute​(String key)
        Returns the value for the specified attribute or null if it does not exist. If the attribute has multiple values specified then the last value specified is returned. For example the following manifest element:
         elementvalue; myattr="value1"; myattr="value2"
         

        specifies two values for the attribute key myattr. In this case value2 will be returned because it is the last value specified for the attribute myattr.

        Parameters:
        key - the attribute key to return the value for
        Returns:
        the attribute value or null
      • getAttributes

        public String[] getAttributes​(String key)
        Returns an array of values for the specified attribute or null if the attribute does not exist.
        Parameters:
        key - the attribute key to return the values for
        Returns:
        the array of attribute values or null
        See Also:
        getAttribute(String)
      • getKeys

        public Enumeration<String> getKeys()
        Returns an enumeration of attribute keys for this manifest element or null if none exist.
        Returns:
        the enumeration of attribute keys or null if none exist.
      • getDirective

        public String getDirective​(String key)
        Returns the value for the specified directive or null if it does not exist. If the directive has multiple values specified then the last value specified is returned. For example the following manifest element:
         elementvalue; mydir:="value1"; mydir:="value2"
         

        specifies two values for the directive key mydir. In this case value2 will be returned because it is the last value specified for the directive mydir.

        Parameters:
        key - the directive key to return the value for
        Returns:
        the directive value or null
      • getDirectives

        public String[] getDirectives​(String key)
        Returns an array of string values for the specified directives or null if it does not exist.
        Parameters:
        key - the directive key to return the values for
        Returns:
        the array of directive values or null
        See Also:
        getDirective(String)
      • getDirectiveKeys

        public Enumeration<String> getDirectiveKeys()
        Return an enumeration of directive keys for this manifest element or null if there are none.
        Returns:
        the enumeration of directive keys or null
      • parseHeader

        public static ManifestElement[] parseHeader​(String header,
                                                    String value)
                                             throws BundleException
        Parses a manifest header value into an array of ManifestElements. Each ManifestElement returned will have a non-null value returned by getValue().
        Parameters:
        header - the header name to parse. This is only specified to provide error messages when the header value is invalid.
        value - the header value to parse.
        Returns:
        the array of ManifestElements that are represented by the header value; null will be returned if the value specified is null or if the value does not parse into one or more ManifestElements.
        Throws:
        BundleException - if the header value is invalid
      • getArrayFromList

        public static String[] getArrayFromList​(String stringList)
        Returns the result of converting a list of comma-separated tokens into an array.
        Parameters:
        stringList - the initial comma-separated string
        Returns:
        the array of string tokens or null if there are none
      • getArrayFromList

        public static String[] getArrayFromList​(String stringList,
                                                String separator)
        Returns the result of converting a list of tokens into an array. The tokens are split using the specified separator.
        Parameters:
        stringList - the initial string list
        separator - the separator to use to split the list into tokens.
        Returns:
        the array of string tokens. If there are none then an empty array is returned.
        Since:
        3.2
      • parseBundleManifest

        public static Map<String,​String> parseBundleManifest​(InputStream manifest,
                                                                   Map<String,​String> headers)
                                                            throws IOException,
                                                                   BundleException
        Parses a bundle manifest and puts the header/value pairs into the supplied Map. Only the main section of the manifest is parsed (up to the first blank line). All other sections are ignored. If a header is duplicated then only the last value is stored in the map.

        The supplied input stream is consumed by this method and will be closed. If the supplied Map is null then a Map is created to put the header/value pairs into.

        Parameters:
        manifest - an input stream for a bundle manifest.
        headers - a map used to put the header/value pairs from the bundle manifest. This value may be null.
        Returns:
        the map with the header/value pairs from the bundle manifest
        Throws:
        BundleException - if the manifest has an invalid syntax
        IOException - if an error occurs while reading the manifest