Class OperatorInstanceof

All Implemented Interfaces:
Opcodes, SpelNode

public class OperatorInstanceof extends Operator
The operator 'instanceof' checks if an object is of the class specified in the right-hand operand, in the same way that instanceof does in Java.
Since:
3.0
Author:
Andy Clement
  • Constructor Details

    • OperatorInstanceof

      public OperatorInstanceof(int startPos, int endPos, SpelNodeImpl... operands)
  • Method Details

    • getValueInternal

      public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException
      Compare the left operand to see it is an instance of the type specified as the right operand. The right operand must be a class.
      Specified by:
      getValueInternal in class SpelNodeImpl
      Parameters:
      state - the expression state
      Returns:
      true if the left operand is an instanceof of the right operand, otherwise false
      Throws:
      EvaluationException - if there is a problem evaluating the expression
    • isCompilable

      public boolean isCompilable()
      Description copied from interface: SpelNode
      Determine if this node can be compiled to bytecode.

      The reasoning in each node may be different but will typically involve checking whether the exit type descriptor of the node is known and any relevant child nodes are compilable.

      The default implementation returns false.

      If you override this method, you must also override SpelNode.generateCode(MethodVisitor, CodeFlow).

      Returns:
      true if this node can be compiled to bytecode
      See Also:
    • generateCode

      public void generateCode(MethodVisitor mv, CodeFlow cf)
      Description copied from interface: SpelNode
      Generate the bytecode for this node into the supplied MethodVisitor.

      Context information about the current expression being compiled is available in the supplied CodeFlow object — for example, information about the type of the object currently on the stack.

      This method will not be invoked unless SpelNode.isCompilable() returns true.

      The default implementation throws an IllegalStateException since SpelNode.isCompilable() returns false by default.

      If you override this method, you must also override SpelNode.isCompilable().

      Parameters:
      mv - the ASM MethodVisitor into which code should be generated
      cf - a context object with information about what is on the stack
      See Also: