QueryDSL uniqueResult()未定义

Question

我有以下代码：

import com.querydsl.jpa.impl.JPAQuery;
...
QCustomer customer = QCustomer.customer;
JPAQuery query = new JPAQuery(entityManager);

Customer result = query.from(customer)
                  .where(customer.firstName.eq("Bob"))
                  .uniqueResult(customer);

然而，在Eclipse中，它说uniqueResult是未定义的。

pom.xml

<build>
    <plugins>
        <plugin>
        <groupId>com.mysema.maven</groupId>
        <artifactId>apt-maven-plugin</artifactId>
        <version>1.1.3</version>
        <executions>
          <execution>
            <goals>
              <goal>process</goal>
            </goals>
            <configuration>
              <outputDirectory>target/generated-sources/java</outputDirectory>
              <processor>com.querydsl.apt.jpa.JPAAnnotationProcessor</processor>
            </configuration>
          </execution>
        </executions>
        <dependencies>
          <dependency>
            <groupId>com.querydsl</groupId>
            <artifactId>querydsl-apt</artifactId>
            <version>4.0.9</version>
          </dependency>
        </dependencies>
      </plugin>
    </plugins>
</build>

<dependency>
    <groupId>com.querydsl</groupId>
    <artifactId>querydsl-jpa</artifactId>
    <version>4.0.9</version>
</dependency>

<dependency>
    <groupId>com.querydsl</groupId>
    <artifactId>querydsl-apt</artifactId>
    <version>4.0.9</version>
</dependency>

<dependency>
    <groupId>com.querydsl</groupId>
    <artifactId>querydsl-core</artifactId>
    <version>4.0.9</version>
</dependency>

Answer 1

我只是继续，避免使用JPAQuery，而是使用JPAQueryFactory。下面是我使用的新代码：

JPAQueryFactory queryFactory = new JPAQueryFactory(entityManager);

QCustomer customer = QCustomer.customer;

List<Study> result = queryFactory.selectFrom(customer)
                                 .where(customer.firstName.eq("Bob"))
                                 .fetchOne();