[OmniFaces utilities 2.2] Check faces messages existence

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[OmniFaces utilities] The isEmpty() method returns true if there are no faces messages, otherwise false
[OmniFaces utilities] The isEmpty(String clientId) method returns true if there are no faces messages for the given client ID, otherwise false
[OmniFaces utilities] The isGlobalEmpty() method returns true if there are no global faces messages, otherwise false

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Methods:

- Messages#isEmpty() - returns true if there are no faces messages, otherwise false

See also: Faces#getContext()

- Messages#isEmpty(String clientId) - returns true if there are no faces messages for the given client ID, otherwise false

See also: Faces#getContext()

- Messages#isGlobalEmpty() - returns true if there are no global faces messages, otherwise false

Usage:

We can use some simple logs to understand how each of the above methods works. We suppose that we have a clientId, myForm:myInput:

LOG.log(Level.INFO, "Messages list is empty ? {0}", Messages.isEmpty());

LOG.log(Level.INFO, "Global messages list is empty ? {0}", Messages.isEmpty(null));

LOG.log(Level.INFO, "Messages list for client Id myForm:myInput is empty ? {0}", Messages.isEmpty("myForm:myInput"));     

·         no messages

Outputs:

Messages list is empty ? true

Global messages list is empty ? true

Messages list for client Id myForm:myInput is empty ? true

·         have some global messages, no clientId specific message (no messages for myForm:myInput)

FacesContext.getCurrentInstance().addMessage(null, 
  new FacesMessage(FacesMessage.SEVERITY_INFO,"Global Info","Dummy info message!"));   

Outputs:

Messages list is empty ? false

Global messages list is empty ? false

Messages list for client Id myForm:myInput is empty ? true

·         have some messages for clientId, myForm:myInput, but no global messages

FacesContext.getCurrentInstance().addMessage("myForm:myInput", 
  new FacesMessage(FacesMessage.SEVERITY_INFO,"Not Global Info","Dummy info message!"));   

Outputs:

Messages list is empty ? false

Global messages list is empty ? true

Messages list for client Id myForm:myInput is empty ? false

·         have some messages for clientId, myForm:myInput and some global messages

FacesContext.getCurrentInstance().addMessage(null, 
  new FacesMessage(FacesMessage.SEVERITY_INFO,"Global Info","Dummy info message!"));   

FacesContext.getCurrentInstance().addMessage("myForm:myInput", 
  new FacesMessage(FacesMessage.SEVERITY_INFO,"Not Global Info","Dummy info message!"));   

    

Outputs:

Messages list is empty ? false

Global messages list is empty ? false

Messages list for client Id myForm:myInput is empty ? false