类 SpelNodeImpl

字段详细资料

• children

  protected SpelNodeImpl[] children

• exitTypeDescriptor

  @Nullable
  protected volatile String exitTypeDescriptor

  Indicates the type descriptor for the result of this expression node. This is set as soon as it is known. For a literal node it is known immediately. For a property access or method invocation it is known after one evaluation of that node.

  The descriptor is like the bytecode form but is slightly easier to work with. It does not include the trailing semicolon (for non array reference types). Some examples: Ljava/lang/String, I, [I

构造器详细资料

• SpelNodeImpl

  public SpelNodeImpl​(int startPos,
                      int endPos,
                      SpelNodeImpl... operands)

方法详细资料

• nextChildIs

  protected boolean nextChildIs​(Class<?>... classes)

  Return true if the next child is one of the specified classes.

• getValue

  @Nullable
  public final Object getValue​(ExpressionState expressionState)
                        throws EvaluationException

  从接口复制的说明: SpelNode
  Evaluate the expression node in the context of the supplied expression state and return the value.

  指定者:

  getValue 在接口中 SpelNode

  参数:

  expressionState - the current expression state (includes the context)

  返回:

  the value of this node evaluated against the specified state

  抛出:

  EvaluationException

• getTypedValue

  public final TypedValue getTypedValue​(ExpressionState expressionState)
                                 throws EvaluationException

  从接口复制的说明: SpelNode
  Evaluate the expression node in the context of the supplied expression state and return the typed value.

  指定者:

  getTypedValue 在接口中 SpelNode

  参数:

  expressionState - the current expression state (includes the context)

  返回:

  the type value of this node evaluated against the specified state

  抛出:

  EvaluationException

• isWritable

  public boolean isWritable​(ExpressionState expressionState)
                     throws EvaluationException

  从接口复制的说明: SpelNode
  Determine if this expression node will support a setValue() call.

  指定者:

  isWritable 在接口中 SpelNode

  参数:

  expressionState - the current expression state (includes the context)

  返回:

  true if the expression node will allow setValue()

  抛出:

  EvaluationException - if something went wrong trying to determine if the node supports writing

• setValue

  public void setValue​(ExpressionState expressionState,
                       @Nullable
                       Object newValue)
                throws EvaluationException

  从接口复制的说明: SpelNode
  Evaluate the expression to a node and then set the new value on that node. For example, if the expression evaluates to a property reference, then the property will be set to the new value.

  指定者:

  setValue 在接口中 SpelNode

  参数:

  expressionState - the current expression state (includes the context)

  newValue - the new value

  抛出:

  EvaluationException - if any problem occurs evaluating the expression or setting the new value

• getChild

  public SpelNode getChild​(int index)

  从接口复制的说明: SpelNode
  Helper method that returns a SpelNode rather than an Antlr Tree node.

  指定者:

  getChild 在接口中 SpelNode

  返回:

  the child node cast to a SpelNode

• getChildCount

  public int getChildCount()

  从接口复制的说明: SpelNode
  Return the number of children under this node.

  指定者:

  getChildCount 在接口中 SpelNode

  返回:

  the child count

• getObjectClass

  @Nullable
  public Class<?> getObjectClass​(@Nullable
                                 Object obj)

  从接口复制的说明: SpelNode
  Determine the class of the object passed in, unless it is already a class object.

  指定者:

  getObjectClass 在接口中 SpelNode

  参数:

  obj - the object that the caller wants the class of

  返回:

  the class of the object if it is not already a class object, or null if the object is null

• getStartPosition

  public int getStartPosition()

  从接口复制的说明: SpelNode
  Return the start position of this AST node in the expression string.

  指定者:

  getStartPosition 在接口中 SpelNode

  返回:

  the start position

• getEndPosition

  public int getEndPosition()

  从接口复制的说明: SpelNode
  Return the end position of this AST node in the expression string.

  指定者:

  getEndPosition 在接口中 SpelNode

  返回:

  the end position

• isCompilable

  public boolean isCompilable()

  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.

  返回:

  true if this node can be compiled to bytecode

• generateCode

  public void generateCode​(MethodVisitor mv,
                           CodeFlow cf)

  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.

  参数:

  mv - the ASM MethodVisitor into which code should be generated

  cf - a context object with info about what is on the stack

• getExitDescriptor

  @Nullable
  public String getExitDescriptor()

• getValue

  @Nullable
  protected final <T> T getValue​(ExpressionState state,
                                 Class<T> desiredReturnType)
                          throws EvaluationException

  抛出:

  EvaluationException

• getValueRef

  protected ValueRef getValueRef​(ExpressionState state)
                          throws EvaluationException

  抛出:

  EvaluationException

• getValueInternal

  public abstract TypedValue getValueInternal​(ExpressionState expressionState)
                                       throws EvaluationException

  抛出:

  EvaluationException

• generateCodeForArguments

  protected static void generateCodeForArguments​(MethodVisitor mv,
                                                 CodeFlow cf,
                                                 Member member,
                                                 SpelNodeImpl[] arguments)

  Generate code that handles building the argument values for the specified method. This method will take account of whether the invoked method is a varargs method and if it is then the argument values will be appropriately packaged into an array.

  参数:

  mv - the method visitor where code should be generated

  cf - the current codeflow

  member - the method or constructor for which arguments are being setup

  arguments - the expression nodes for the expression supplied argument values

• generateCodeForArgument

  protected static void generateCodeForArgument​(MethodVisitor mv,
                                                CodeFlow cf,
                                                SpelNodeImpl argument,
                                                String paramDesc)

  Ask an argument to generate its bytecode and then follow it up with any boxing/unboxing/checkcasting to ensure it matches the expected parameter descriptor.