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@Beanc Annotation
<p>
The {@link oaj.annotation.Beanc @Beanc} annotation is used to
map constructor arguments to property names on bean with read-only properties.
Since method parameter names are lost during compilation, this annotation essentially redefines
them so that they are available at runtime.
</p>
<p>
The definition of a read-only bean is a bean with properties with only getters, like shown below:
</p>
<p class='bpcode w800'>
<jc>// Our read-only bean.</jc>
<jk>public class</jk> Person {
<jk>private final</jk> String <jf>name</jf>;
<jk>private final int</jk> <jf>age</jf>;
<ja>@Beanc</ja>(properties=<js>"name,age"</js>})
<jk>public</jk> Person(String name, <jk>int</jk> age) {
<jk>this</jk>.<jf>name</jf> = name;
<jk>this</jk>.<jf>age</jf> = age;
}
<jc>// Read only properties.</jc>
<jc>// Getters, but no setters.</jc>
<jk>public</jk> String getName() {
<jk>return</jk> <jf>name</jf>;
}
<jk>public int</jk> getAge() {
<jk>return</jk> <jf>age</jf>;
}
}
</p>
<p class='bpcode w800'>
<jc>// Parsing into a read-only bean.</jc>
String json = <js>"{name:'John Smith',age:45}"</js>;
Person p = JsonParser.<jsf>DEFAULT</jsf>.parse(json);
String name = p.getName(); <jc>// "John Smith"</jc>
<jk>int</jk> age = p.getAge(); <jc>// 45</jc>
</p>
<p>
Beans can also be defined with a combination of read-only and read-write properties.
</p>
<p>
The {@link oaj.annotation.Name @Name} annotation can also be used instead of <c><ja>@Beanc</ja>(properties)</c>:
</p>
<p class='bpcode w800'>
<ja>@Beanc</ja>
<jk>public</jk> Person(<ja>@Name</ja>(<js>"name"</js>) String name, <ja>@Name</ja>(<js>"age"</js>) <jk>int</jk> age) {
<jk>this</jk>.<jf>name</jf> = name;
<jk>this</jk>.<jf>age</jf> = age;
}
</p>
<p>
If neither <c><ja>@Beanc</ja>(properties)</c> or <ja>@Name</ja> is used to identify the bean property names,
we will try to use the parameter names if they are available in the bytecode.
</p>