LikePredicate.java

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
package org.hibernate.query.criteria.internal.predicate;

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

import org.hibernate.query.criteria.internal.CriteriaBuilderImpl;
import org.hibernate.query.criteria.internal.ParameterRegistry;
import org.hibernate.query.criteria.internal.Renderable;
import org.hibernate.query.criteria.internal.compile.RenderingContext;
import org.hibernate.query.criteria.internal.expression.LiteralExpression;

/**
 * Models a SQL <tt>LIKE</tt> expression.
 *
 * @author Steve Ebersole
 */
public class LikePredicate extends AbstractSimplePredicate implements Serializable {
	private final Expression<String> matchExpression;
	private final Expression<String> pattern;
	private final Expression<Character> escapeCharacter;

	public LikePredicate(
			CriteriaBuilderImpl criteriaBuilder,
			Expression<String> matchExpression,
			Expression<String> pattern) {
		this( criteriaBuilder, matchExpression, pattern, null );
	}

	public LikePredicate(
			CriteriaBuilderImpl criteriaBuilder,
			Expression<String> matchExpression,
			String pattern) {
		this( criteriaBuilder, matchExpression, new LiteralExpression<String>( criteriaBuilder, pattern) );
	}

	public LikePredicate(
			CriteriaBuilderImpl criteriaBuilder,
			Expression<String> matchExpression,
			Expression<String> pattern,
			Expression<Character> escapeCharacter) {
		super( criteriaBuilder );
		this.matchExpression = matchExpression;
		this.pattern = pattern;
		this.escapeCharacter = escapeCharacter;
	}

	public LikePredicate(
			CriteriaBuilderImpl criteriaBuilder,
			Expression<String> matchExpression,
			Expression<String> pattern,
			char escapeCharacter) {
		this(
				criteriaBuilder,
				matchExpression,
				pattern,
				new LiteralExpression<Character>( criteriaBuilder, escapeCharacter )
		);
	}

	public LikePredicate(
			CriteriaBuilderImpl criteriaBuilder,
			Expression<String> matchExpression,
			String pattern,
			char escapeCharacter) {
		this(
				criteriaBuilder,
				matchExpression,
				new LiteralExpression<String>( criteriaBuilder, pattern ),
				new LiteralExpression<Character>( criteriaBuilder, escapeCharacter )
		);
	}

	public LikePredicate(
			CriteriaBuilderImpl criteriaBuilder,
			Expression<String> matchExpression,
			String pattern,
			Expression<Character> escapeCharacter) {
		this(
				criteriaBuilder,
				matchExpression,
				new LiteralExpression<String>( criteriaBuilder, pattern ),
				escapeCharacter
		);
	}

	public Expression<Character> getEscapeCharacter() {
		return escapeCharacter;
	}

	public Expression<String> getMatchExpression() {
		return matchExpression;
	}

	public Expression<String> getPattern() {
		return pattern;
	}

	public void registerParameters(ParameterRegistry registry) {
		Helper.possibleParameter( getEscapeCharacter(), registry );
		Helper.possibleParameter( getMatchExpression(), registry );
		Helper.possibleParameter( getPattern(), registry );
	}

	@Override
	public String render(boolean isNegated, RenderingContext renderingContext) {
		final String operator = isNegated ? " not like " : " like ";
		StringBuilder buffer = new StringBuilder();
		buffer.append( ( (Renderable) getMatchExpression() ).render( renderingContext ) )
				.append( operator )
				.append( ( (Renderable) getPattern() ).render( renderingContext ) );
		if ( escapeCharacter != null ) {
			buffer.append( " escape " )
					.append( ( (Renderable) getEscapeCharacter() ).render( renderingContext ) );
		}
		return buffer.toString();
	}
}