spring-framework/spring-framework-reference/src/beans-standard-annotations.xml

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<section id="beans-standard-annotations">
  <title>Using JSR 330 standard annotations</title>
  
  <para>Starting from Spring 3.0, Spring offers support for JSR-330 standard annotations  (Dependency Injection).
  Those annotations are scanned in the same way as the Spring annotations. You just need to have the relevant jars in your classpath.
  </para>
  <note>
  If you are using Maven, the <interfacename>javax.inject</interfacename> artifact is available on the standard Maven repository (<ulink url="http://repo1.maven.org/maven2/javax/inject/javax.inject/1/">http://repo1.maven.org/maven2/javax/inject/javax.inject/1/</ulink>). You just need to add the following dependency to your file pom.xml:
  <programlisting language="xml">
		&lt;dependency&gt;
			&lt;groupId&gt;javax.inject&lt;/groupId&gt;
			&lt;artifactId&gt;javax.inject&lt;/artifactId&gt;
			&lt;version&gt;1&lt;/version&gt;
		&lt;/dependency&gt;
  </programlisting>
  </note>
  
  <section id="beans-inject-named">
    <title>Dependency Injection with <interfacename>@Inject</interfacename> and <interfacename>@Named</interfacename></title>
    <para>
    Instead of <interfacename>@Autowired</interfacename>, <interfacename>javax.inject.Inject</interfacename> may be used as follows:
    
    <programlisting language="java">
  import javax.inject.Inject;
  public class SimpleMovieLister {

  private MovieFinder movieFinder;

  @Inject
  public void setMovieFinder(MovieFinder movieFinder) {
      this.movieFinder = movieFinder;
  }
  <lineannotation>// ...</lineannotation>
}</programlisting>

	As for <interfacename>@Autowired</interfacename>, it is possible to use <interfacename>@Inject</interfacename> at the class-level, field-level, method-level and constructor-argument level.

	If you would like to use a qualified name for the dependency that should be injected, you should use the <interfacename>@Named</interfacename> annotation as follows:
    <programlisting language="java">
  import javax.inject.Inject;
  import javax.inject.Named;
  
  public class SimpleMovieLister {

  private MovieFinder movieFinder;

  @Inject
  public void setMovieFinder(@Named("main") MovieFinder movieFinder) {
      this.movieFinder = movieFinder;
  }
  <lineannotation>// ...</lineannotation>
}</programlisting>	
	
    </para>
  </section>

<section id="beans-named">
    <title><interfacename>@Named</interfacename>: a standard equivalent to the <interfacename>@Component</interfacename> annotation</title>
    <para>
    Instead of <interfacename>@Component</interfacename>, <interfacename>javax.inject.Named</interfacename> may be used as follows:
        <programlisting language="java">
  import javax.inject.Inject;
  import javax.inject.Named;
  
  @Named("movieListener")
  public class SimpleMovieLister {

  private MovieFinder movieFinder;

  @Inject
  public void setMovieFinder(MovieFinder movieFinder) {
      this.movieFinder = movieFinder;
  }
  <lineannotation>// ...</lineannotation>
}</programlisting>	
</para>
<para>
It is very common to use <interfacename>@Component</interfacename> without specifying a name for the component. <interfacename>@Named</interfacename> can be used in a similar fashion:
    <programlisting language="java">
  import javax.inject.Inject;
  import javax.inject.Named;
  
  @Named
  public class SimpleMovieLister {

  private MovieFinder movieFinder;

  @Inject
  public void setMovieFinder(MovieFinder movieFinder) {
      this.movieFinder = movieFinder;
  }
  <lineannotation>// ...</lineannotation>
}
</programlisting>
</para>
<para>
When using <interfacename>@Named</interfacename>, it is possible to use component-scanning in the exact same way as when using Spring annotations:
    <programlisting language="xml">
    &lt;beans&gt;
    	&lt;context:component-scan base-package="org.example"/&gt;
    &lt;/beans&gt;
</programlisting>	
</para>
</section>
<section id="beans-standard-annotations-limitations">
    <title>Limitations of the standard approach</title>
	<para>When working with standard annotations, it is important to know that some significant  features are not available as shown in the table below:</para>
	
	 <para><table id="annotations-comparison">
          <title>Spring annotations vs standard annotations</title>

          <tgroup cols="3">

            <colspec colnum="1" colwidth="0.7*" />

            <colspec colnum="2" colwidth="0.6*" />

            <colspec colnum="3" colwidth="1.5*" />

            <thead>
              <row>
                <entry>Spring</entry>

                <entry>javax.inject.*</entry>

                <entry>javax.inject restrictions / comments</entry>
              </row>
            </thead>

            <tbody>
              <row>
                <entry>@Autowired</entry>

                <entry>@Inject</entry>

                <entry>@Inject has no 'required' attribute</entry>
              </row>
              <row>
                <entry>@Component</entry>

                <entry>@Named</entry>

                <entry></entry>
              </row>
              <row>
                <entry>@Scope("singleton")</entry>

                <entry>@Singleton</entry>

                <entry>
                	<para>
                		jsr-330 default scope is like Spring's <interfacename>prototype</interfacename>. However, in order to keep it consistent with Spring's general defaults, a jsr-330 bean declared in the Spring container is a <interfacename>singleton</interfacename> by default. In order to use another scope than <interfacename>singleton</interfacename>, you should use Spring's <interfacename>@Scope</interfacename> annotation.
                	</para>
                	<para>
                		<interfacename>javax.inject</interfacename> also provides a <ulink url="http://download.oracle.com/javaee/6/api/javax/inject/Scope.html">@Scope</ulink> annotation. Nevertheless, this one only aims to be used for creating your own annotations. 
                	</para>
                </entry>
              </row>              
              <row>
                <entry>@Qualifier</entry>

                <entry>@Named</entry>

                <entry></entry>
              </row>  
               <row>
                <entry>@Value</entry>

                <entry>-</entry>

                <entry>no equivalent</entry>
              </row> 
               <row>
                <entry>@Required</entry>

                <entry>-</entry>

                <entry>no equivalent</entry>
              </row> 
               <row>
                <entry>@Lazy</entry>

                <entry>-</entry>

                <entry>no equivalent</entry>
              </row> 
            </tbody>     
          </tgroup>
         </table>
        </para>
	
	</section>
</section>