/*
* Copyright 2015, The Querydsl Team (http://www.querydsl.com/team)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.querydsl.jdo;
import com.querydsl.core.Tuple;
import com.querydsl.core.types.EntityPath;
import com.querydsl.core.types.Expression;
import com.querydsl.core.types.dsl.Expressions;
/**
* Common JDO expressions
*/
public final class JDOExpressions {
/**
* Create a new detached {@link JDOQuery} instance with the given projection
*
* @param expr projection
* @param <T>
* @return select(expr)
*/
public static <T> JDOQuery<T> select(Expression<T> expr) {
return new JDOQuery<Void>().select(expr);
}
/**
* Create a new detached {@link JDOQuery} instance with the given projection
*
* @param exprs projection
* @return select(exprs)
*/
public static JDOQuery<Tuple> select(Expression<?>... exprs) {
return new JDOQuery<Void>().select(exprs);
}
/**
* Create a new detached {@link JDOQuery} instance with the given projection
*
* @param expr projection
* @param <T>
* @return select(distinct expr)
*/
public static <T> JDOQuery<T> selectDistinct(Expression<T> expr) {
return select(expr).distinct();
}
/**
* Create a new detached {@link JDOQuery} instance with the given projection
*
* @param exprs projection
* @return select(distinct exprs)
*/
public static JDOQuery<Tuple> selectDistinct(Expression<?>... exprs) {
return select(exprs).distinct();
}
/**
* Create a new detached {@link JDOQuery} instance with the given projection 0
*
* @return select(0)
*/
public static JDOQuery<Integer> selectZero() {
return select(Expressions.ZERO);
}
/**
* Create a new detached {@link JDOQuery} instance with the projection 1
*
* @return select(1)
*/
public static JDOQuery<Integer> selectOne() {
return select(Expressions.ONE);
}
/**
* Create a new detached {@link JDOQuery} instance with the given projection
*
* @param expr projection and source
* @param <T>
* @return select(expr).from(expr)
*/
public static <T> JDOQuery<T> selectFrom(EntityPath<T> expr) {
return select(expr).from(expr);
}
private JDOExpressions() { }
}