Expression (Apache Calcite API)

java.lang.Object
- org.apache.calcite.linq4j.tree.AbstractNode
- - org.apache.calcite.linq4j.tree.Expression

All Implemented Interfaces:

Node

Direct Known Subclasses:

BinaryExpression, ConstantExpression, DefaultExpression, DynamicExpression, IndexExpression, InvocationExpression, LambdaExpression, ListInitExpression, MemberExpression, MemberInitExpression, MethodCallExpression, NewArrayExpression, NewExpression, ParameterExpression, TernaryExpression, TypeBinaryExpression, UnaryExpression
```
public abstract class Expression
extends AbstractNode
```
Analogous to LINQ's System.Linq.Expression.

Field Summary
- Fields inherited from class org.apache.calcite.linq4j.tree.AbstractNode
  nodeType, type

Constructor Summary

Constructors
Constructor Description

Expression(ExpressionType nodeType, Type type)
Creates an Expression.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`abstract Expression`	`accept(Shuttle shuttle)`
`boolean`	`canReduce()`	Indicates that the node can be reduced to a simpler node.

Methods inherited from class org.apache.calcite.linq4j.tree.AbstractNode
accept, accept, accept0, equals, evaluate, getNodeType, getType, hashCode, toString

Methods inherited from interface org.apache.calcite.linq4j.tree.Node
accept

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - Expression
```
public Expression(ExpressionType nodeType,
                  Type type)
```
    Creates an Expression.
    The type of the expression may, at the caller's discretion, be a regular class (because Class implements Type) or it may be a different implementation that retains information about type parameters.
    
    Parameters:
    
    nodeType - Node type
    
    type - Type of the expression
- Method Detail
  - accept
```
public abstract Expression accept(Shuttle shuttle)
```
    Specified by:
    
    accept in interface Node
    
    Overrides:
    
    accept in class AbstractNode
  - canReduce
```
public boolean canReduce()
```
    Indicates that the node can be reduced to a simpler node. If this returns true, Reduce() can be called to produce the reduced form.