Package com.tangosol.coherence.rest.util.extractor

Class MvelExtractor

java.lang.Object
com.tangosol.util.Base
com.tangosol.util.BitHelper
com.tangosol.util.ExternalizableHelper
com.tangosol.util.extractor.AbstractExtractor
com.tangosol.coherence.rest.util.extractor.MvelExtractor
All Implemented Interfaces:
CanonicallyNamed, ExternalizableLite, PortableObject, QueryMapComparator, Remote.Function, Remote.ToDoubleFunction, Remote.ToIntFunction, Remote.ToLongFunction, ValueExtractor, Serializable, Comparator, Function, ToDoubleFunction, ToIntFunction, ToLongFunction
public class MvelExtractor extends AbstractExtractor implements ValueExtractor, ExternalizableLite, PortableObject
MVEL-based ValueExtractor implementation.
Author:
as 2011.06.21
See Also:

  • Field Details

    • m_sExpr

      protected String m_sExpr
      The MVEL expression to evaluate.

    • m_oExpr

      protected transient Serializable m_oExpr
      Compiled expression.

  • Constructor Details

    • MvelExtractor

      public MvelExtractor()
      Default constructor (necessary for the ExternalizableLite and PortableObject interfaces).

    • MvelExtractor

      public MvelExtractor(String sExpr)
      Construct a MvelExtractor based on an MVEL expression.
      Parameters:
      sExpr - the MVEL expression to evaluate

    • MvelExtractor

      public MvelExtractor(String sExpr, int nTarget)
      Construct a MvelExtractor based on an MVEL expression and an entry extraction target.
      Parameters:
      sExpr - the MVEL expression to evaluate
      nTarget - one of the AbstractExtractor.VALUE or AbstractExtractor.KEY values

  • Method Details

    • extract

      public Object extract(Object oTarget)
      Extract the value from the passed object. The returned value may be null. For intrinsic types, the returned value is expected to be a standard wrapper type in the same manner that reflection works; for example, int would be returned as a java.lang.Integer.
      Specified by:
      extract in interface ValueExtractor
      Overrides:
      extract in class AbstractExtractor
      Parameters:
      oTarget - the object to extract the value from
      Returns:
      the extracted value; null is an acceptable value

    • getCompiledExpression

      protected Serializable getCompiledExpression()
      Return a compiled MVEL expression.
      Returns:
      compiled MVEL expression

    • equals

      public boolean equals(Object o)
      Compare the MvelExtractor with another object to determine equality. Two MvelExtractor objects, e1 and e2 are considered equal iff e1.extract(o) equals e2.extract(o) for all values of o.
      Specified by:
      equals in interface Comparator
      Specified by:
      equals in interface ValueExtractor
      Overrides:
      equals in class AbstractExtractor
      Parameters:
      o - the reference object with which to compare
      Returns:
      true iff this MvelExtractor and the passed object are equivalent MvelExtractor instances

    • hashCode

      public int hashCode()
      Determine a hash value for the MvelExtractor object according to the general Object.hashCode() contract.
      Specified by:
      hashCode in interface ValueExtractor
      Overrides:
      hashCode in class AbstractExtractor
      Returns:
      an integer hash value for this MvelExtractor object

    • toString

      public String toString()
      Provide a human-readable description of this MvelExtractor object.
      Overrides:
      toString in class Object
      Returns:
      a human-readable description of this MvelExtractor object

    • readExternal

      public void readExternal(DataInput in) throws IOException
      Restore the contents of this object by loading the object's state from the passed DataInput object.
      Specified by:
      readExternal in interface ExternalizableLite
      Parameters:
      in - the DataInput stream to read data from in order to restore the state of this object
      Throws:
      IOException - if an I/O exception occurs
      NotActiveException - if the object is not in its initial state, and therefore cannot be deserialized into

    • writeExternal

      public void writeExternal(DataOutput out) throws IOException
      Save the contents of this object by storing the object's state into the passed DataOutput object.
      Specified by:
      writeExternal in interface ExternalizableLite
      Parameters:
      out - the DataOutput stream to write the state of this object to
      Throws:
      IOException - if an I/O exception occurs

    • readExternal

      public void readExternal(PofReader in) throws IOException
      Restore the contents of a user type instance by reading its state using the specified PofReader object.
      Specified by:
      readExternal in interface PortableObject
      Parameters:
      in - the PofReader from which to read the object's state
      Throws:
      IOException - if an I/O error occurs

    • writeExternal

      public void writeExternal(PofWriter out) throws IOException
      Save the contents of a POF user type instance by writing its state using the specified PofWriter object.
      Specified by:
      writeExternal in interface PortableObject
      Parameters:
      out - the PofWriter to which to write the object's state
      Throws:
      IOException - if an I/O error occurs