托管 Bean 页面传值的使用方法和技巧(2)

MyBean1.java:

package mypackage;
import javax.faces.context.FacesContext;
public class MyBean1 
{    
    // Using VariableResolver. NOTE: this is deprecated since JSF 1.2!   
    public void action1() 
    {       
        FacesContext context = FacesContext.getCurrentInstance();       
        MyBean2 myBean2 = (MyBean2) context.getApplication().getVariableResolver().resolveVariable(context, "myBean2");
        myBean2.getText().setValue("action1");   
    }   
    
    // Using ValueBinding. NOTE: this is deprecated since JSF 1.2!   
    public void action2() 
    {       
        FacesContext context = FacesContext.getCurrentInstance(); 
        MyBean2 myBean2 = (MyBean2) context.getApplication().createValueBinding("#{myBean2}").getValue(context);       
        myBean2.getText().setValue("action2");   
    }   
    
    // Using ELResolver. NOTE: this is implemented since JSF 1.2!  
    public void action3() 
    {       
        FacesContext context = FacesContext.getCurrentInstance();
        MyBean2 myBean2 = (MyBean2) context.getELContext().getELResolver().getValue(context.getELContext(), null, "myBean2");
        myBean2.getText().setValue("action3");
    }   
    
    // Using ValueExpression. NOTE: this is implemented since JSF 1.2!   
    public void action4() 
    {       
        FacesContext context = FacesContext.getCurrentInstance();
        MyBean2 myBean2 = (MyBean2) context.getApplication().getExpressionFactory().createValueExpression(context.getELContext(), "#{myBean2}", MyBean2.class).getValue(context.getELContext());
        myBean2.getText().setValue("action4");   
    }  
    
    // Using RequestMap. NOTE: myBean2 should be request scoped!   
    public void action5() 
    {       
        Object object = FacesContext.getCurrentInstance().getExternalContext().getRequestMap().get("myBean2");
        // This only works if myBean2 is request scoped.       
        if (object != null) 
        {           
            MyBean2 myBean2 = (MyBean2) object;
            myBean2.getText().setValue("action5");       
        }   
    }   
    
    // Using SessionMap. NOTE: myBean2 should be session scoped!   
    public void action6() 
    ...{       
        Object object =  FacesContext.getCurrentInstance().getExternalContext().getSessionMap().get("myBean2");
        // This only works if myBean2 is session scoped.       
        if (object != null) 
        {         
            MyBean2 myBean2 = (MyBean2) object;
            myBean2.getText().setValue("action6"); 
        }   
    }

}

MyBean2.java:

package mypackage;
import javax.faces.component.html.HtmlOutputText;
public class MyBean2 
{   
    private HtmlOutputText text;   
    
    public HtmlOutputText getText() 
    {       
        return text;   
    }   
    
    public void setText(HtmlOutputText text) 
    {       
        this.text = text;   
    }
}