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 <H2>
 <FONT SIZE="-1">
 javax.inject</FONT>
 <BR>
 Annotation Type Inject</H2>
 <HR>
 <DL>
 <DT><PRE><FONT SIZE="-1">@Target(value={METHOD,CONSTRUCTOR,FIELD})
 @Retention(value=RUNTIME)
 @Documented
 </FONT>public @interface <B>Inject</B></DL>
 </PRE>

 <P>
 Identifies injectable constructors, methods, and fields. Applies to static
  as well as instance members. An injectable member may have any access
  modifier (private, package-private, protected, public). Constructors are
  injected first, followed by fields, and then methods. Fields and methods
  in superclasses are injected before those in subclasses. Ordering of
  injection among fields and among methods in the same class is not specified.
  Which values are injected depends upon the injector implementation and its
  configuration.

  <p>Injectable constructors are annotated with <code>@Inject</code> and accept
  zero or more dependencies as arguments. <code>@Inject</code> can apply to at most
  one constructor per class.

  <p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">@Inject
        <i>ConstructorModifiers<sub>opt</sub></i>
        <i>SimpleTypeName</i>(<i>FormalParameterList<sub>opt</sub></i>)
        <i>Throws<sub>opt</sub></i>
        <i>ConstructorBody</i></blockquote></tt>

  <p><code>@Inject</code> is optional for public, no-argument constructors when no
  other constructors are present. This enables injectors to invoke default
  constructors.

  <p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">
        @Inject<sub><i>opt</i></sub>
        <i>Annotations<sub>opt</sub></i>
        public
        <i>SimpleTypeName</i>()
        <i>Throws<sub>opt</sub></i>
        <i>ConstructorBody</i></blockquote></tt>

  <p>Injectable fields:
  <ul>
    <li>are annotated with <code>@Inject</code>.
    <li>are not final.
    <li>may have any otherwise valid name.</li></ul>

  <p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">@Inject
        <i>FieldModifiers<sub>opt</sub></i>
        <i>Type</i>
        <i>VariableDeclarators</i>;</blockquote></tt>

  <p>Injectable methods:
  <ul>
    <li>are annotated with <code>@Inject</code>.</li>
    <li>are not abstract.</li>
    <li>do not declare type parameters of their own.</li>
    <li>return <code>void</code>.</li>
    <li>may have any otherwise valid name.</li>
    <li>accept zero or more dependencies as arguments.</li></ul>

  <p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">@Inject
        <i>MethodModifiers<sub>opt</sub></i>
        void
        <i>Identifier</i>(<i>FormalParameterList<sub>opt</sub></i>)
        <i>Throws<sub>opt</sub></i>
        <i>MethodBody</i></blockquote></tt>

  <p>For example:

  <pre>
    public class Car {
      // Injectable constructor
      &#064;Inject public Car(Engine engine) { ... }

      // Injectable field
      &#064;Inject private Provider&lt;Seat> seatProvider;

      // Injectable package-private method
      &#064;Inject void install(Windshield windshield, Trunk trunk) { ... }
    }</pre>

  <p>A method annotated with <code>@Inject</code> that overrides another method
  annotated with <code>@Inject</code> will only be injected once per injection
  request per instance. A method with <i>no</i> <code>@Inject</code> annotation
  that overrides a method annotated with <code>@Inject</code> will not be
  injected.

  <p>Injection of members annotated with <code>@Inject</code> is required by
  default. This behavior can be overridden by setting <A HREF="../../javax/inject/Inject.html#optional()"><CODE>optional</CODE></A> equal to <code>true</code>.

  <p>Detecting and resolving circular dependencies is left as an exercize for
  the injector implementation. Circular dependencies between two constructors
  is an obvious problem, but you can also have a circular dependency between
  injectable fields or methods:

  <pre>
    class A {
      &#064;Inject B b;
    }
    class B {
      &#064;Inject A a;
    }</pre>

  <p>When constructing an instance of <code>A</code>, a naive injector
  implementation might go into an infinite loop constructing an instance of
  <code>B</code> to set on <code>A</code>, a second instance of <code>A</code> to set on
  <code>B</code>, a second instance of <code>B</code> to set on the second instance of
  <code>A</code>, and so on.

  <p>A conservative injector might detect the circular dependency at build
  time and generate an error, at which point the programmer could break the
  circular dependency by injecting <A HREF="../../javax/inject/Provider.html" title="interface in javax.inject"><CODE>Provider&lt;A></CODE></A> or <code>Provider&lt;B&gt;</code> instead of <code>A</code> or <code>B</code> respectively. Calling <A HREF="../../javax/inject/Provider.html#get()"><CODE>get()</CODE></A> on the provider directly from the constructor or
  method it was injected into defeats the provider's ability to break up
  circular dependencies. In the case of method or field injection, scoping
  one of the dependencies (using <A HREF="../../javax/inject/Singleton.html" title="annotation in javax.inject">singleton scope</A>, for
  example) may also enable a valid circular relationship.
 <P>

 <P>
 <DL>
 <DT><B>See Also:</B><DD><A HREF="../../javax/inject/Qualifier.html" title="annotation in javax.inject"><CODE>@Qualifier</CODE></A>,
 <A HREF="../../javax/inject/Provider.html" title="interface in javax.inject"><CODE>Provider</CODE></A></DL>
 <HR>

 <P>
 <!-- =========== ANNOTATION TYPE OPTIONAL MEMBER SUMMARY =========== -->

 <A NAME="annotation_type_optional_element_summary"><!-- --></A>
 <TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
 <TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
 <TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
 <B>Optional Element Summary</B></FONT></TH>
 </TR>
 <TR BGCOLOR="white" CLASS="TableRowColor">
 <TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
 <CODE>&nbsp;boolean</CODE></FONT></TD>
 <TD><CODE><B><A HREF="../../javax/inject/Inject.html#optional()">optional</A></B></CODE>

 <BR>
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Whether or not injection is optional.</TD>
 </TR>
 </TABLE>
 &nbsp;
 <P>
 <A NAME="optional()"><!-- --></A><H3>
 optional</H3>
 <PRE>
 public abstract boolean <B>optional</B></PRE>
 <DL>
 <DD>Whether or not injection is optional. If <code>true</code>, the injector's
  behavior varies depending on the type of injection point:

  <p><ul>
    <li><b>Constructors:</b> <i>Not allowed</i></li>
    <li><b>Fields:</b> If a dependency matching the field can't
      be found, the injector will not set the field.</li>
    <li><b>Methods:</b> If a dependency matching a method parameter can't
      be found, the injector will skip invoking the method entirely, even
      if other arguments could be provided.</li>
  </ul>

  <p>If an applicable dependency has been configured but the injector
  encounters an error while resolving the dependency (a transitive
  dependency could be missing, for example), the injector should generate
  an error, not skip the injection. For example:

  <pre>
    &#064;Inject(optional=true) Gps gps;</pre>

  <p>If a Gps isn't available at all, the injector will simply not set the
  <code>gps</code> field. If a Gps is available but an algorithm it depends
  upon can't be found, the injector will generate an error.
 <P>
 <DD><DL>
 </DL>
 </DD>
 <DD><DL>
 </DL>
 <DL>
 <DT><B>Default:</B><DD>false</DD>
 </DL>
 </DL>
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	<H2>
	<FONT SIZE="-1">
	javax.inject</FONT>
	<BR>
	Annotation Type Inject</H2>
	<HR>
	<DL>
	<DT><PRE><FONT SIZE="-1">@Target(value={METHOD,CONSTRUCTOR,FIELD})
	@Retention(value=RUNTIME)
	@Documented
	</FONT>public @interface <B>Inject</B></DL>
	</PRE>

	<P>
	Identifies injectable constructors, methods, and fields. Applies to static
	as well as instance members. An injectable member may have any access
	modifier (private, package-private, protected, public). Constructors are
	injected first, followed by fields, and then methods. Fields and methods
	in superclasses are injected before those in subclasses. Ordering of
	injection among fields and among methods in the same class is not specified.
	Which values are injected depends upon the injector implementation and its
	configuration.

	<p>Injectable constructors are annotated with <code>@Inject</code> and accept
	zero or more dependencies as arguments. <code>@Inject</code> can apply to at most
	one constructor per class.

	<p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">@Inject
	<i>ConstructorModifiers<sub>opt</sub></i>
	<i>SimpleTypeName</i>(<i>FormalParameterList<sub>opt</sub></i>)
	<i>Throws<sub>opt</sub></i>
	<i>ConstructorBody</i></blockquote></tt>

	<p><code>@Inject</code> is optional for public, no-argument constructors when no
	other constructors are present. This enables injectors to invoke default
	constructors.

	<p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">
	@Inject<sub><i>opt</i></sub>
	<i>Annotations<sub>opt</sub></i>
	public
	<i>SimpleTypeName</i>()
	<i>Throws<sub>opt</sub></i>
	<i>ConstructorBody</i></blockquote></tt>

	<p>Injectable fields:
	<ul>
	<li>are annotated with <code>@Inject</code>.
	<li>are not final.
	<li>may have any otherwise valid name.</li></ul>

	<p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">@Inject
	<i>FieldModifiers<sub>opt</sub></i>
	<i>Type</i>
	<i>VariableDeclarators</i>;</blockquote></tt>

	<p>Injectable methods:
	<ul>
	<li>are annotated with <code>@Inject</code>.</li>
	<li>are not abstract.</li>
	<li>do not declare type parameters of their own.</li>
	<li>return <code>void</code>.</li>
	<li>may have any otherwise valid name.</li>
	<li>accept zero or more dependencies as arguments.</li></ul>

	<p><tt><blockquote style="padding-left: 2em; text-indent: -2em;">@Inject
	<i>MethodModifiers<sub>opt</sub></i>
	void
	<i>Identifier</i>(<i>FormalParameterList<sub>opt</sub></i>)
	<i>Throws<sub>opt</sub></i>
	<i>MethodBody</i></blockquote></tt>

	<p>For example:

	<pre>
	public class Car {
	// Injectable constructor
	@Inject public Car(Engine engine) { ... }

	// Injectable field
	@Inject private Provider<Seat> seatProvider;

	// Injectable package-private method
	@Inject void install(Windshield windshield, Trunk trunk) { ... }
	}</pre>

	<p>A method annotated with <code>@Inject</code> that overrides another method
	annotated with <code>@Inject</code> will only be injected once per injection
	request per instance. A method with <i>no</i> <code>@Inject</code> annotation
	that overrides a method annotated with <code>@Inject</code> will not be
	injected.

	<p>Injection of members annotated with <code>@Inject</code> is required by
	default. This behavior can be overridden by setting <A HREF="../../javax/inject/Inject.html#optional()"><CODE>optional</CODE></A> equal to <code>true</code>.

	<p>Detecting and resolving circular dependencies is left as an exercize for
	the injector implementation. Circular dependencies between two constructors
	is an obvious problem, but you can also have a circular dependency between
	injectable fields or methods:

	<pre>
	class A {
	@Inject B b;
	}
	class B {
	@Inject A a;
	}</pre>

	<p>When constructing an instance of <code>A</code>, a naive injector
	implementation might go into an infinite loop constructing an instance of
	<code>B</code> to set on <code>A</code>, a second instance of <code>A</code> to set on
	<code>B</code>, a second instance of <code>B</code> to set on the second instance of
	<code>A</code>, and so on.

	<p>A conservative injector might detect the circular dependency at build
	time and generate an error, at which point the programmer could break the
	circular dependency by injecting <A HREF="../../javax/inject/Provider.html" title="interface in javax.inject"><CODE>Provider<A></CODE></A> or <code>Provider<B></code> instead of <code>A</code> or <code>B</code> respectively. Calling <A HREF="../../javax/inject/Provider.html#get()"><CODE>get()</CODE></A> on the provider directly from the constructor or
	method it was injected into defeats the provider's ability to break up
	circular dependencies. In the case of method or field injection, scoping
	one of the dependencies (using <A HREF="../../javax/inject/Singleton.html" title="annotation in javax.inject">singleton scope</A>, for
	example) may also enable a valid circular relationship.
	<P>

	<P>
	<DL>
	<DT><B>See Also:</B><DD><A HREF="../../javax/inject/Qualifier.html" title="annotation in javax.inject"><CODE>@Qualifier</CODE></A>,
	<A HREF="../../javax/inject/Provider.html" title="interface in javax.inject"><CODE>Provider</CODE></A></DL>
	<HR>

	<P>
	<!-- =========== ANNOTATION TYPE OPTIONAL MEMBER SUMMARY =========== -->

	<A NAME="annotation_type_optional_element_summary"><!-- --></A>
	<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
	<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
	<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
	<B>Optional Element Summary</B></FONT></TH>
	</TR>
	<TR BGCOLOR="white" CLASS="TableRowColor">
	<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
	<CODE> boolean</CODE></FONT></TD>
	<TD><CODE><B><A HREF="../../javax/inject/Inject.html#optional()">optional</A></B></CODE>

	<BR>
	Whether or not injection is optional.</TD>
	</TR>
	</TABLE>

	<P>
	<A NAME="optional()"><!-- --></A><H3>
	optional</H3>
	<PRE>
	public abstract boolean <B>optional</B></PRE>
	<DL>
	<DD>Whether or not injection is optional. If <code>true</code>, the injector's
	behavior varies depending on the type of injection point:

	<p><ul>
	<li><b>Constructors:</b> <i>Not allowed</i></li>
	<li><b>Fields:</b> If a dependency matching the field can't
	be found, the injector will not set the field.</li>
	<li><b>Methods:</b> If a dependency matching a method parameter can't
	be found, the injector will skip invoking the method entirely, even
	if other arguments could be provided.</li>
	</ul>

	<p>If an applicable dependency has been configured but the injector
	encounters an error while resolving the dependency (a transitive
	dependency could be missing, for example), the injector should generate
	an error, not skip the injection. For example:

	<pre>
	@Inject(optional=true) Gps gps;</pre>

	<p>If a Gps isn't available at all, the injector will simply not set the
	<code>gps</code> field. If a Gps is available but an algorithm it depends
	upon can't be found, the injector will generate an error.
	<P>
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	<DT><B>Default:</B><DD>false</DD>
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