Class CompoundExpression

java.lang.Object
org.springframework.expression.spel.ast.SpelNodeImpl
org.springframework.expression.spel.ast.CompoundExpression
All Implemented Interfaces:
Opcodes, SpelNode

public class CompoundExpression extends SpelNodeImpl
Represents a DOT separated expression sequence, such as property1.property2.methodOne() or property1?.property2?.methodOne() when the null-safe navigation operator is used.

May also contain array/collection/map indexers, such as property1[0].property2['key'].

Since:
3.0
Author:
Andy Clement, Sam Brannen
  • Constructor Details

    • CompoundExpression

      public CompoundExpression(int startPos, int endPos, SpelNodeImpl... expressionComponents)
  • Method Details

    • getValueRef

      protected ValueRef getValueRef(ExpressionState state) throws EvaluationException
      Overrides:
      getValueRef in class SpelNodeImpl
      Throws:
      EvaluationException
    • getValueInternal

      public TypedValue getValueInternal(ExpressionState state) throws EvaluationException
      Evaluates a compound expression. This involves evaluating each piece in turn and the return value from each piece is the active context object for the subsequent piece.
      Specified by:
      getValueInternal in class SpelNodeImpl
      Parameters:
      state - the state in which the expression is being evaluated
      Returns:
      the final value from the last piece of the compound expression
      Throws:
      EvaluationException
    • setValueInternal

      public TypedValue setValueInternal(ExpressionState state, Supplier<TypedValue> valueSupplier) throws EvaluationException
      Description copied from class: SpelNodeImpl
      Evaluate the expression to a node and then set the new value created by the specified Supplier on that node.

      For example, if the expression evaluates to a property reference, then the property will be set to the new value.

      Favor this method over SpelNodeImpl.setValue(ExpressionState, Object) when the value should be lazily computed.

      By default, this method throws a SpelEvaluationException, effectively disabling this feature. Subclasses may override this method to provide an actual implementation.

      Overrides:
      setValueInternal in class SpelNodeImpl
      Parameters:
      state - the current expression state (includes the context)
      valueSupplier - a supplier of the new value
      Throws:
      EvaluationException - if any problem occurs evaluating the expression or setting the new value
    • isWritable

      public boolean isWritable(ExpressionState state) throws EvaluationException
      Description copied from interface: SpelNode
      Determine if this expression node will support a setValue() call.
      Specified by:
      isWritable in interface SpelNode
      Overrides:
      isWritable in class SpelNodeImpl
      Parameters:
      state - the current expression state (includes the context)
      Returns:
      true if the expression node will allow setValue()
      Throws:
      EvaluationException - if something went wrong trying to determine if the node supports writing
    • toStringAST

      public String toStringAST()
      Description copied from interface: SpelNode
      Return the string form of this AST node.
      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, e.g. including 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