Class FrameworkUtil.FilterImpl

java.lang.Object
org.osgi.framework.FrameworkUtil.FilterImpl
All Implemented Interfaces:
Filter
Enclosing class:
FrameworkUtil
private static final class FrameworkUtil.FilterImpl extends Object implements Filter
RFC 1960-based Filter. Filter objects can be created by calling the constructor with the desired filter string. A Filter object can be called numerous times to determine if the match argument matches the filter string that was used to create the Filter object.

The syntax of a filter string is the string representation of LDAP search filters as defined in RFC 1960: A String Representation of LDAP Search Filters (available at http://www.ietf.org/rfc/rfc1960.txt). It should be noted that RFC 2254: A String Representation of LDAP Search Filters (available at http://www.ietf.org/rfc/rfc2254.txt) supersedes RFC 1960 but only adds extensible matching and is not applicable for this API.

The string representation of an LDAP search filter is defined by the following grammar. It uses a prefix format. 

  <filter> ::= '(' <filtercomp> ')'
  <filtercomp> ::= <and> | <or> | <not> | <item>
  <and> ::= '&' <filterlist>
  <or> ::= '|' <filterlist>
  <not> ::= '!' <filter>
  <filterlist> ::= <filter> | <filter> <filterlist>
  <item> ::= <simple> | <present> | <substring>
  <simple> ::= <attr> <filtertype> <value>
  <filtertype> ::= <equal> | <approx> | <greater> | <less>
  <equal> ::= '='
  <approx> ::= '˜='
  <greater> ::= '>='
  <less> ::= '<='
  <present> ::= <attr> '=*'
  <substring> ::= <attr> '=' <initial> <any> <final>
  <initial> ::= NULL | <value>
  <any> ::= '*' <starval>
  <starval> ::= NULL | <value> '*' <starval>
  <final> ::= NULL | <value>
&lt;attr&gt; is a string representing an attribute, or key, in the properties objects of the registered services. Attribute names are not case sensitive; that is cn and CN both refer to the same attribute. &lt;value&gt; is a string representing the value, or part of one, of a key in the properties objects of the registered services. If a &lt;value&gt; must contain one of the characters ' *' or '(' or ')', these characters should be escaped by preceding them with the backslash '\' character. Note that although both the &lt;substring&gt; and &lt;present&gt; productions can produce the 'attr=*' construct, this construct is used only to denote a presence filter.

Examples of LDAP filters are: 

  "(cn=Babs Jensen)"
  "(!(cn=Tim Howes))"
  "(&(" + Constants.OBJECTCLASS + "=Person)(|(sn=Jensen)(cn=Babs J*)))"
  "(o=univ*of*mich*)"

The approximate match (~=) is implementation specific but should at least ignore case and white space differences. Optional are codes like soundex or other smart "closeness" comparisons.

Comparison of values is not straightforward. Strings are compared differently than numbers and it is possible for a key to have multiple values. Note that that keys in the match argument must always be strings. The comparison is defined by the object type of the key's value. The following rules apply for comparison:

Property Value Type Comparison Type
String String comparison
Integer, Long, Float, Double, Byte, Short, BigInteger, BigDecimal numerical comparison
Character character comparison
Boolean equality comparisons only
[] (array) recursively applied to values
Collection recursively applied to values
Note: arrays of primitives are also supported.
A filter matches a key that has multiple values if it matches at least one of those values. For example, 
Dictionary d = new Hashtable();
d.put("cn", new String[] {"a", "b", "c"});
d will match (cn=a) and also (cn=b)

A filter component that references a key having an unrecognizable data type will evaluate to false .

Since:
1.3

  • Field Details

  • Constructor Details

    • FilterImpl

      FilterImpl(int operation, String attr, Object value)

  • Method Details

    • newInstance

      static FrameworkUtil.FilterImpl newInstance(String filterString) throws InvalidSyntaxException
      Constructs a FrameworkUtil.FilterImpl object. This filter object may be used to match a ServiceReference or a Dictionary.

      If the filter cannot be parsed, an InvalidSyntaxException will be thrown with a human readable message where the filter became unparsable.

      Parameters:
      filterString - the filter string.
      Throws:
      InvalidSyntaxException - If the filter parameter contains an invalid filter string that cannot be parsed.

    • match

      public boolean match(ServiceReference<?> reference)
      Filter using a service's properties.

      This Filter is executed using the keys and values of the referenced service's properties. The keys are looked up in a case insensitive manner.

      Specified by:
      match in interface Filter
      Parameters:
      reference - The reference to the service whose properties are used in the match.
      Returns:
      true if the service's properties match this Filter; false otherwise.

    • match

      public boolean match(Dictionary<String,?> dictionary)
      Filter using a Dictionary with case insensitive key lookup. This Filter is executed using the specified Dictionary's keys and values. The keys are looked up in a case insensitive manner.
      Specified by:
      match in interface Filter
      Parameters:
      dictionary - The Dictionary whose key/value pairs are used in the match.
      Returns:
      true if the Dictionary's values match this filter; false otherwise.
      Throws:
      IllegalArgumentException - If dictionary contains case variants of the same key name.

    • matchCase

      public boolean matchCase(Dictionary<String,?> dictionary)
      Filter using a Dictionary. This Filter is executed using the specified Dictionary's keys and values. The keys are looked up in a normal manner respecting case.
      Specified by:
      matchCase in interface Filter
      Parameters:
      dictionary - The Dictionary whose key/value pairs are used in the match.
      Returns:
      true if the Dictionary's values match this filter; false otherwise.
      Since:
      1.3

    • matches

      public boolean matches(Map<String,?> map)
      Filter using a Map. This Filter is executed using the specified Map's keys and values. The keys are looked up in a normal manner respecting case.
      Specified by:
      matches in interface Filter
      Parameters:
      map - The Map whose key/value pairs are used in the match. Maps with null key or values are not supported. A null value is considered not present to the filter.
      Returns:
      true if the Map's values match this filter; false otherwise.
      Since:
      1.6

    • toString

      public String toString()
      Returns this Filter's filter string.

      The filter string is normalized by removing whitespace which does not affect the meaning of the filter.

      Specified by:
      toString in interface Filter
      Overrides:
      toString in class Object
      Returns:
      This Filter's filter string.

    • normalize

      private StringBuffer normalize()
      Returns this Filter's normalized filter string.

      The filter string is normalized by removing whitespace which does not affect the meaning of the filter.

      Returns:
      This Filter's filter string.

    • equals

      public boolean equals(Object obj)
      Compares this Filter to another Filter.

      This implementation returns the result of calling this.toString().equals(obj.toString().

      Specified by:
      equals in interface Filter
      Overrides:
      equals in class Object
      Parameters:
      obj - The object to compare against this Filter.
      Returns:
      If the other object is a Filter object, then returns the result of calling this.toString().equals(obj.toString(); false otherwise.

    • hashCode

      public int hashCode()
      Returns the hashCode for this Filter.

      This implementation returns the result of calling this.toString().hashCode().

      Specified by:
      hashCode in interface Filter
      Overrides:
      hashCode in class Object
      Returns:
      The hashCode of this Filter.

    • encodeValue

      private static String encodeValue(String value)
      Encode the value string such that '(', '*', ')' and '\' are escaped.
      Parameters:
      value - unencoded value string.
      Returns:
      encoded value string.

    • compare

      private boolean compare(int operation, Object value1, Object value2)

    • compare_Collection

      private boolean compare_Collection(int operation, Collection<?> collection, Object value2)

    • compare_ObjectArray

      private boolean compare_ObjectArray(int operation, Object[] array, Object value2)

    • compare_PrimitiveArray

      private boolean compare_PrimitiveArray(int operation, Class<?> type, Object primarray, Object value2)

    • compare_String

      private boolean compare_String(int operation, String string, Object value2)

    • compare_Integer

      private boolean compare_Integer(int operation, int intval, Object value2)

    • compare_Long

      private boolean compare_Long(int operation, long longval, Object value2)

    • compare_Byte

      private boolean compare_Byte(int operation, byte byteval, Object value2)

    • compare_Short

      private boolean compare_Short(int operation, short shortval, Object value2)

    • compare_Character

      private boolean compare_Character(int operation, char charval, Object value2)

    • compare_Boolean

      private boolean compare_Boolean(int operation, boolean boolval, Object value2)

    • compare_Float

      private boolean compare_Float(int operation, float floatval, Object value2)

    • compare_Double

      private boolean compare_Double(int operation, double doubleval, Object value2)

    • valueOf

      private static Object valueOf(Class<?> target, String value2)

    • setAccessible

      private static void setAccessible(AccessibleObject accessible)

    • compare_Comparable

      private boolean compare_Comparable(int operation, Comparable<Object> value1, Object value2)

    • compare_Unknown

      private boolean compare_Unknown(int operation, Object value1, Object value2)

    • approxString

      private static String approxString(String input)
      Map a string for an APPROX (~=) comparison. This implementation removes white spaces. This is the minimum implementation allowed by the OSGi spec.
      Parameters:
      input - Input string.
      Returns:
      String ready for APPROX comparison.