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Question of the Week Archive

Topic:  

What does the property="*" mean?

Question:  

In a JavaServer Page^TM (JSP), I see the "*" in the setProperty tag. Can someone explain this to me? I can't find any specific documentation about this. Why is the * used? Are there any other valid values for this property?

Answer:

The JSP setProperty tag with a "*" indicates that all properties in the JSP page will be set to its respective method in the bean. In other words, the "*" is a wildcard that copies all similarly-named parameters into the bean. If the "*" is there, then all the inputs in the JSP will be stored in the bean. You can also individually store inputs. Here is an example:

If you have:

 
<jsp:setProperty name="mybean" property="*" /> 

 
<INPUT TYPE ="TEXT" NAME="login" value=""> 
<INPUT TYPE ="PASSWORD" NAME="password" value=""> 

public String value; 
public String password; 

void setLogin(String value){ 
	login = value; 
} 

void setPassword(String value){ 
	password=value; 
} 

For more information:

JavaServer Pages^TM Technology

JavaBeans^TM

JSP Architecture Quiz, including source code, which uses property="*".

Many thanks to JDC member chetan and mozkill for contributing to this answer.

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