org.springframework.expression.spel.ast

Class OpMinus

  • All Implemented Interfaces:
    Opcodes, SpelNode


    public class OpMinus
    extends Operator
    The minus operator supports:
    • subtraction of numbers
    • subtraction of an int from a string of one character (effectively decreasing that character), so 'd'-3='a'

    It can be used as a unary operator for numbers. The standard promotions are performed when the operand types vary (double-int=double). For other options it defers to the registered overloader.

    Since:
    3.0
    Author:
    Andy Clement, Juergen Hoeller, Giovanni Dall'Oglio Risso
    • Constructor Detail

      • OpMinus

        public OpMinus(int pos,
                       SpelNodeImpl... operands)
    • Method Detail

      • toStringAST

        public java.lang.String toStringAST()
        Description copied from class: Operator
        String format for all operators is the same '(' [operand] [operator] [operand] ')'.
        Specified by:
        toStringAST in interface SpelNode
        Overrides:
        toStringAST in class Operator
        Returns:
        the string form
      • isCompilable

        public boolean isCompilable()
        Description copied from class: SpelNodeImpl
        Check whether a 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.
        Overrides:
        isCompilable in class SpelNodeImpl
        Returns:
        true if this node can be compiled to bytecode
      • generateCode

        public void generateCode(MethodVisitor mv,
                                 CodeFlow cf)
        Description copied from class: SpelNodeImpl
        Generate the bytecode for this node into the supplied visitor. Context info about the current expression being compiled is available in the codeflow object. For example it will include information about the type of the object currently on the stack.
        Overrides:
        generateCode in class SpelNodeImpl
        Parameters:
        mv - the ASM MethodVisitor into which code should be generated
        cf - a context object with info about what is on the stack