Package org.apache.struts2.util
Interface ValueStack
- All Known Implementing Classes:
- OgnlValueStack
public interface ValueStack
ValueStack allows multiple beans to be pushed in and dynamic EL expressions to be evaluated against it. When
 evaluating an expression, the stack will be searched down the stack, from the latest objects pushed in to the
 earliest, looking for a bean with a getter or setter for the given property or a method of the given name (depending
 on the expression being evaluated).
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Field SummaryFields
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Method SummaryModifier and TypeMethodDescriptionfindString(String expr) findString(String expr, boolean throwExceptionOnFailure) Find a value by evaluating the given expression against the stack in the default search order.Find a value by evaluating the given expression against the stack in the default search order.Gets the context for this value stack.Gets the override map if anyone exists.getRoot()Get the CompoundRoot which holds the objects pushed onto the stackpeek()Get the object on the top of the stack without changing the stack.pop()Get the object on the top of the stack and remove it from the stack.voidPut this object onto the top of the stackvoidSets an object on the stack with the given key so it is retrievable byfindValue(String),findValue(String, Class)voidsetDefaultType(Class defaultType) Sets the default type to convert to if no type is provided when getting a value.voidsetExprOverrides(Map<Object, Object> overrides) Set a override map containingkey -> valuesthat takes precedent when doing find operations on the ValueStack.voidsetParameter(String expr, Object value) Attempts to set a property on a bean in the stack with the given expression using the default search order.voidAttempts to set a property on a bean in the stack with the given expression using the default search order.voidAttempts to set a property on a bean in the stack with the given expression using the default search order.intsize()Get the number of objects in the stack
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Field Details- 
VALUE_STACK- See Also:
 
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REPORT_ERRORS_ON_NO_PROP- See Also:
 
 
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Method Details- 
getContextGets the context for this value stack. The context holds all the information in the value stack and it's surroundings.- Returns:
- the context.
 
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getActionContextActionContext getActionContext()
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setDefaultTypeSets the default type to convert to if no type is provided when getting a value.- Parameters:
- defaultType- the new default type
 
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setExprOverridesSet a override map containingkey -> valuesthat takes precedent when doing find operations on the ValueStack.See the unit test for ValueStackTest for examples. - Parameters:
- overrides- overrides map.
 
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getExprOverridesGets the override map if anyone exists.- Returns:
- the override map, null if not set.
 
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getRootCompoundRoot getRoot()Get the CompoundRoot which holds the objects pushed onto the stack- Returns:
- the root
 
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setValueAttempts to set a property on a bean in the stack with the given expression using the default search order.- Parameters:
- expr- the expression defining the path to the property to be set.
- value- the value to be set into the named property
 
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setParameterAttempts to set a property on a bean in the stack with the given expression using the default search order. N.B.: unlike #setValue(String,Object) it doesn't allow eval expression.- Parameters:
- expr- the expression defining the path to the property to be set.
- value- the value to be set into the named property
 
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setValueAttempts to set a property on a bean in the stack with the given expression using the default search order.- Parameters:
- expr- the expression defining the path to the property to be set.
- value- the value to be set into the named property
- throwExceptionOnFailure- a flag to tell whether an exception should be thrown if there is no property with the given name.
 
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findString
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findString
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findValueFind a value by evaluating the given expression against the stack in the default search order.- Parameters:
- expr- the expression giving the path of properties to navigate to find the property value to return
- Returns:
- the result of evaluating the expression
 
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findValue
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findValueFind a value by evaluating the given expression against the stack in the default search order.- Parameters:
- expr- the expression giving the path of properties to navigate to find the property value to return
- asType- the type to convert the return value to
- Returns:
- the result of evaluating the expression
 
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findValue
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peekObject peek()Get the object on the top of the stack without changing the stack.- Returns:
- the object on the top.
- See Also:
 
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popObject pop()Get the object on the top of the stack and remove it from the stack.- Returns:
- the object on the top of the stack
- See Also:
 
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pushPut this object onto the top of the stack- Parameters:
- o- the object to be pushed onto the stack
- See Also:
 
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setSets an object on the stack with the given key so it is retrievable byfindValue(String),findValue(String, Class)- Parameters:
- key- the key
- o- the object
 
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sizeint size()Get the number of objects in the stack- Returns:
- the number of objects in the stack
 
 
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