ADF 11g Quicky 3 : Adding Error, Info and Warning messages

How can we add a message programatically ? Last week I got this question for the second time in a months time. I decided to write a short blogpost on how this works.

Adding messages is very easy, you just need to know how it works.
You can add a message to your faces context by creating a new FacesMessage. Set the severity (ERROR, WARNING, INFO or FATAL ), set the message text, and if nessecary a message detail. The fragment below shows the code for an ERROR message.

1:   public void setMessagesErr(ActionEvent actionEvent) {  
2:    String msg = "This is a message";  
3:    AdfFacesContext adfFacesContext = null;  
4:    adfFacesContext = AdfFacesContext.getCurrentInstance();  
5:    FacesContext ctx = FacesContext.getCurrentInstance();  
6:    FacesMessage fm =   
7:      new FacesMessage(FacesMessage.SEVERITY_ERROR, msg, "");  
8:    ctx.addMessage(null, fm);  
9:   }  

I created a simple page with a couple of buttons to show the result of setting the message. When the button is pressed the message is shown.

1:  <?xml version='1.0' encoding='UTF-8'?>  
2:  <jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1"  
3:       xmlns:af="http://xmlns.oracle.com/adf/faces/rich"  
4:       xmlns:f="http://java.sun.com/jsf/core">  
5:   <af:inputText label="Label 1" id="it1"></af:inputText>  
6:   <af:inputText label="Label 2" id="it2"  
7:          binding="#{pageFlowScope.msgsBean.showMessage}"></af:inputText>  
8:   <af:inputText label="Label 3" id="it3"></af:inputText>  
9:   <af:commandButton text="error" id="cb1"  
10:            actionListener="#{pageFlowScope.msgsBean.setMessagesErr}"/>  
11:   <af:commandButton text="info" id="cb2"  
12:            actionListener="#{pageFlowScope.msgsBean.setMessagesInf}"/>  
13:   <af:commandButton text="warn" id="cb3"  
            actionListener="#{pageFlowScope.msgsBean.setMessagesWrn}"/>  
14:  15:                    actionListener="#{pageFlowScope.msgsBean.setMessagesFat}"/>
16:   <af:commandButton text="warn for comp" id="cb4"  
17:            actionListener="#{pageFlowScope.msgsBean.setMessagesWrnForComp}"/>  
18:  </jsp:root>  

A special case is the message that is directly related to a component. For that I use the button that calls the "setMessageForComp" method combined with an inputtext field that is bound to a bean : binding="#{pageFlowScope.msgsBean.showMessage}.
The code behind this button is slightly different from the one show in the java fragment earlier. The important part is that the message is specifically added to the component : getShowMessage().getClientId(ctx).

1:   public void setMessagesWrnForComp(ActionEvent actionEvent) {  
2:    // Add event code here...c  
3:    String msg = "This is a message";  
4:    AdfFacesContext adfFacesContext = null;  
5:    adfFacesContext = AdfFacesContext.getCurrentInstance();  
6:    FacesContext ctx = FacesContext.getCurrentInstance();  
7:    FacesMessage fm =   
8:      new FacesMessage(FacesMessage.SEVERITY_WARN, msg, "");   
9:    ctx.addMessage(getShowMessage().getClientId(ctx), fm);    
10:   }  
11:   public void setShowMessage(RichInputText showMessage) {  
12:    this.showMessage = showMessage;  
13:   }  
14:   public RichInputText getShowMessage() {  
15:    return showMessage;  
16:   }  
17:   public void setMessagesWrnForComp(ActionEvent actionEvent) {  
18:    // Add event code here...c  
19:    String msg = "This is a message";  
20:    AdfFacesContext adfFacesContext = null;  
21:    adfFacesContext = AdfFacesContext.getCurrentInstance();  
22:    FacesContext ctx = FacesContext.getCurrentInstance();  
23:    FacesMessage fm =   
24:      new FacesMessage(FacesMessage.SEVERITY_WARN, msg, "");  
25:    ctx.addMessage(getShowMessage().getClientId(ctx), fm);    
26:   }  
27:   public void setShowMessage(RichInputText showMessage) {  
28:    this.showMessage = showMessage;  
29:   }  
30:   public RichInputText getShowMessage() {  
31:    return showMessage;  
32:   }  

The code for this quicky can be downloaded here.