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 * Hibernate, Relational Persistence for Idiomatic Java
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package org.hibernate.jpa.criteria.predicate;

import java.io.Serializable;
import javax.persistence.criteria.Expression;

import org.hibernate.jpa.criteria.CriteriaBuilderImpl;
import org.hibernate.jpa.criteria.ParameterRegistry;
import org.hibernate.jpa.criteria.Renderable;
import org.hibernate.jpa.criteria.compile.RenderingContext;

Predicate to assert the explicit value of a boolean expression:
  • x = true
  • x = false
  • x <> true
  • x <> false
Author:Steve Ebersole
/** * Predicate to assert the explicit value of a boolean expression:<ul> * <li>x = true</li> * <li>x = false</li> * <li>x <> true</li> * <li>x <> false</li> * </ul> * * @author Steve Ebersole */
public class BooleanAssertionPredicate extends AbstractSimplePredicate implements Serializable { private final Expression<Boolean> expression; private final Boolean assertedValue; public BooleanAssertionPredicate( CriteriaBuilderImpl criteriaBuilder, Expression<Boolean> expression, Boolean assertedValue) { super( criteriaBuilder ); this.expression = expression; this.assertedValue = assertedValue; } public Expression<Boolean> getExpression() { return expression; } public Boolean getAssertedValue() { return assertedValue; } @Override public void registerParameters(ParameterRegistry registry) { Helper.possibleParameter( expression, registry ); } @Override public String render(boolean isNegated, RenderingContext renderingContext) { final String operator = isNegated ? " <> " : " = "; final String assertionLiteral = assertedValue ? "true" : "false"; return ( (Renderable) expression ).render( renderingContext ) + operator + assertionLiteral; } }