jsfparameter-passingmanaged-bean

Passing data between managed components in JSF


Is it actually possible to pass any data between managed components in JSF? If yes, how to achieve this?

Could anyone provide any sample?


Solution

  • There are several ways. If the managed beans are related to each other, cleanest way would be injection. There are different ways depending on JSF version and whether beans are managed by CDI.

    CDI

    Just use @Inject.

    @Named
    @SessionScoped
    public class Bean1 {
    
        // ...
    }
    
    @Named
    @RequestScoped
    public class Bean2 {
    
        @Inject
        private Bean1 bean1; // No getter/setter needed.
    }
    

    Other way around can also, the scope of the source and target bean doesn't matter because CDI injects under the covers a proxy.

    JSF 2.x

    Use @ManagedProperty.

    @ManagedBean
    @SessionScoped
    public class Bean1 {
    
        // ...
    }
    
    @ManagedBean
    @RequestScoped
    public class Bean2 {
    
        @ManagedProperty("#{bean1}")
        private Bean1 bean1; // Getter/setter required.
    }
    

    Other way around is not possible in this specific example because JSF injects the physical instance and not a proxy instance. You can only inject a bean of the same or broader scope into a bean of a particular scope.

    JSF 1.x

    Use <managed-property> in faces-config.xml.

    public class Bean1 {
    
        // ...
    }
    
    public class Bean2 {
    
        private Bean1 bean1; // Getter/setter required.
    }
    
    <managed-bean>
        <managed-bean-name>bean1</managed-bean-name>
        <managed-bean-class>com.example.Bean1</managed-bean-class>
        <managed-bean-scope>session</managed-bean-scope>
    </managed-bean>
    
    <managed-bean>
        <managed-bean-name>bean2</managed-bean-name>
        <managed-bean-class>com.example.Bean2</managed-bean-class>
        <managed-bean-scope>request</managed-bean-scope>
        <managed-property>
            <property-name>bean1</property-name>
            <value>#{bean1}</value>
        </managed-property>
    </managed-bean>
    

    See also: