NamedQuery (Java EE 5)

Java EE API

previous page next page

Overview

Package

Class

Tree

Deprecated

Index

Help

PREV CLASS NEXT CLASS

FRAMES NO FRAMES

SUMMARY: REQUIRED | OPTIONAL

DETAIL: ELEMENT

javax.persistence Annotation Type NamedQuery

@Target(value=TYPE) @Retention(value=RUNTIME) public @interface NamedQuery

Implements: Annotation

@Target(value=TYPE)
@Retention(value=RUNTIME)

此类用于指定使用 Java Persistence 查询语言编写的指定查询，它在元数据中表示为静态查询。查询名称的范围限制在持久性单元内。

以下是定义使用 Java Persistence 查询语言编写的指定查询的示例：

    @NamedQuery(
            name="findAllCustomersWithName",
            query="SELECT c FROM Customer c WHERE c.name LIKE :custName"
    )

以下是使用指定查询的示例：

    @PersistenceContext
    public EntityManager em;
    ...
    customers = em.createNamedQuery("findAllCustomersWithName")
            .setParameter("custName", "Smith")
            .getResultList();

since

Java Persistence 1.0

英文文档：

Is used to specify a named query in the Java Persistence query language, which is a static query expressed in metadata. Query names are scoped to the persistence unit.

The following is an example of the definition of a named query in the Java Persistence query language:

    @NamedQuery(
            name="findAllCustomersWithName",
            query="SELECT c FROM Customer c WHERE c.name LIKE :custName"
    )

The following is an example of the use of a named query:

    @PersistenceContext
    public EntityManager em;
    ...
    customers = em.createNamedQuery("findAllCustomersWithName")
            .setParameter("custName", "Smith")
            .getResultList();

Since:: Java Persistence 1.0

Required Element Summary
`String`	`name` Refers to the query when using the `EntityManager` methods that create query objects.
`String`	`query` The query string in the Java Persistence query language