org.datanucleus.query.expression
Class ClassExpression

java.lang.Object
  org.datanucleus.query.expression.Expression
      org.datanucleus.query.expression.ClassExpression

public class ClassExpression
extends Expression

Expression representing a candidate in a FROM clause. This is used in JPQL where we have a "from" clause like

 SELECT ... FROM Product p JOIN p.reviews r

so the ClassExpression is for alias "p" of type Product. The class name is stored in the Symbol, keyed by this alias. Can have a JoinExpression to its right.

Nested Class Summary

Nested classes/interfaces inherited from class org.datanucleus.query.expression.Expression

Expression.DyadicOperator, Expression.MonadicOperator, Expression.Operator

Field Summary

Fields inherited from class org.datanucleus.query.expression.Expression

left, LOCALISER, op, OP_ADD, OP_AND, OP_COM, OP_CONCAT, OP_DISTINCT, OP_DIV, OP_EQ, OP_GT, OP_GTEQ, OP_IN, OP_IS, OP_ISNOT, OP_LIKE, OP_LT, OP_LTEQ, OP_MOD, OP_MUL, OP_NEG, OP_NOT, OP_NOTEQ, OP_OR, OP_SUB, right, symbol

Constructor Summary

ClassExpression(java.lang.String alias)

Method Summary

Symbol	bind(SymbolTable symtbl) Method to bind the expression to the symbol table as appropriate.
java.lang.String	getAlias()
java.lang.String	getCandidateExpression()
void	setCandidateExpression(java.lang.String expr)
void	setJoinExpression(JoinExpression expr) Set the right expression to the provided join.
java.lang.String	toString()

Methods inherited from class org.datanucleus.query.expression.Expression

evaluate, getLeft, getOperator, getRight, getSymbol, setAlias

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ClassExpression

public ClassExpression(java.lang.String alias)

Method Detail

setCandidateExpression

public void setCandidateExpression(java.lang.String expr)

getCandidateExpression

public java.lang.String getCandidateExpression()

setJoinExpression

public void setJoinExpression(JoinExpression expr)

Set the right expression to the provided join.

Parameters:

expr - Join information

getAlias

public java.lang.String getAlias()

Overrides:

getAlias in class Expression

bind

public Symbol bind(SymbolTable symtbl)

Method to bind the expression to the symbol table as appropriate.

Specified by:

bind in class Expression

Parameters:

symtbl - Symbol table

Returns:

The symbol for this expression

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object