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| xml |
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| xml |
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| title | Probably wrong! |
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<s:textfield key="state.label" name="state" value="CAca"/>
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If a textfield is passed the value attribute "CAca", the framework will look for a property named getCa. Generally, this is not what we mean. What we mean to do is pass a literal String. In the expression language, literals are placed within quotes
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| xml |
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| xml |
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| title | Passing a literal value the right way |
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<s:textfield key="state.label" name="state" value="%{'CAca'}" />
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Another approach would be to use the idiom value="'CAca'", but, in this case, using the expression notation is recommended.
...
- All String attribute types are parsed for the "%{ ... }" notation.
- All non-String attribute types are not parsed, but evaluated directly as an expression
- The exception to rule #2 is that if the non-String attribute uses the escape notion "{%{}", the notation is ignored as redundant, and the content evaluated.
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Please remember about altSyntax option that can change when value is evaluated as an expression - Alt Syntax |
Expression Language Notations
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<p>Username: ${user.username}</p> |
| A JavaBean object in a standard context in Freemarker, Velocity, or JSTL EL (Not OGNL). |
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<s:textfield name="username"/> |
| A username property on the Value Stack. |
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<s:url id="es" action="Hello">
<s:param name="request_locale">
es
</s:param>
</s:url>
<s:a href="%{es}">Espanol</s:a> |
| Another way to refer to a property placed on the Value Stack. |
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<s:property
namevalue="#session.user.username" /> |
| The username property of the User object in the Session context. |
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<s:select
label="FooBar" name="foo"
list="#{'username':'trillian',
'username':'zaphod'}" /> |
| A static Map, as in put("username","trillian"). |
Disallowed property names
The following names of property are disallowed:
- parameters
- application
- session
- struts
- request
- servletRequest
- servletResponse
The below code will not work:
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<s:iterator value="parameters"/>
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public class MyAction {
private String[] parameters;
public String[] getParameters() {
return parameters;
}
}
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