Package org.apache.openjpa.datacache

Class QueryKey

java.lang.Object
org.apache.openjpa.datacache.QueryKey
All Implemented Interfaces:
Externalizable, Serializable
public class QueryKey extends Object implements Externalizable
This class stores information about a particular invocation of a query. It contains a reference to the external properties of the query that was executed, as well as any parameters used to execute that query, with one exception: first-class objects used as parameter values are converted to OIDs.
Author:
Patrick Linskey
See Also:

  • Constructor Details

    • QueryKey

      public QueryKey()
      Public constructor for externalization only.

  • Method Details

    • newInstance

      public static QueryKey newInstance(Query q)
      Return a key for the given query, or null if it is not cacheable.

    • newInstance

      public static QueryKey newInstance(Query q, Object[] args)
      Return a key for the given query, or null if it is not cacheable.

    • newInstance

      public static QueryKey newInstance(Query q, Map<Object,Object> args)
      Return a key for the given query, or null if it is not cacheable.

    • getCandidateTypeName

      public String getCandidateTypeName()
      Returns the candidate class name for this query.

    • getTimeout

      public int getTimeout()
      Return the amount of time this key is good for.

    • changeInvalidatesQuery

      public boolean changeInvalidatesQuery(Collection<Class<?>> changed)
      Returns true if modifications to any of the classes in changed results in a possible invalidation of this query; otherwise returns false. Invalidation is possible if one or more of the classes in this query key's access path has been changed.

    • equals

      public boolean equals(Object ob)
      Determine equality based on identifying information. Keys created for queries that specify a candidate collection are always not equal.
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Define a hashing algorithm corresponding to the equals(java.lang.Object) method defined above.
      Overrides:
      hashCode in class Object

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • writeExternal

      public void writeExternal(ObjectOutput out) throws IOException
      Specified by:
      writeExternal in interface Externalizable
      Throws:
      IOException

    • readExternal

      public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException
      Specified by:
      readExternal in interface Externalizable
      Throws:
      IOException
      ClassNotFoundException

    • getAcessPathClassNames

      public Set<String> getAcessPathClassNames()
      Returns the set of the accessPathClassnames that exists in the query
      Returns:
      -- Returns a set of accesspath classnames.