org.datanucleus.query.expression
Class ClassExpression

java.lang.Object
  extended by org.datanucleus.query.expression.Expression
      extended by 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


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