All Superinterfaces:

BasicDetails, Named

All Known Subinterfaces:

MutableModuleItem<T>

All Known Implementing Classes:

AbstractModuleItem, CommandModuleItem, DefaultMutableModuleItem
```
public interface ModuleItem<T>
extends BasicDetails
```
A ModuleItem represents metadata about one input or output of a module.

Author:

Aivar Grislis, Curtis Rueden

Method Summary

All Methods Instance Methods Abstract Methods Default Methods Deprecated Methods
Modifier and Type	Method	Description
`void`	`callback(Module module)`	Invokes this item's callback function, if any, on the given module.
`String`	`getCallback()`	Gets the function that is called whenever this item changes.
`List<T>`	`getChoices()`	Gets the list of possible values.
`int`	`getColumnCount()`	Gets the preferred width of the input field in characters (if applicable).
`T`	`getDefaultValue()`	Gets the default value.
`Type`	`getGenericType()`	Gets the type of the item, including Java generic parameters.
`ModuleInfo`	`getInfo()`	Gets the `ModuleInfo` to which this item belongs.
`String`	`getInitializer()`	Gets the function that is called to initialize the item's value.
`ItemIO`	`getIOType()`	Gets the input/output type of the item.
`T`	`getMaximumValue()`	Gets the maximum allowed value (if applicable).
`T`	`getMinimumValue()`	Gets the minimum allowed value (if applicable).
`String`	`getPersistKey()`	Gets the key to use for saving the value persistently.
`T`	`getSoftMaximum()`	Gets the "soft" maximum value (if applicable).
`T`	`getSoftMinimum()`	Gets the "soft" minimum value (if applicable).
`Number`	`getStepSize()`	Gets the preferred step size to use when rendering the item in a user interface (if applicable).
`Class<T>`	`getType()`	Gets the type of the item.
`String`	`getValidater()`	Gets the function that is called to validate the item's value.
`T`	`getValue(Module module)`	Gets the item's current value with respect to the given module.
`ItemVisibility`	`getVisibility()`	Gets the visibility of the item.
`String`	`getWidgetStyle()`	Gets the preferred widget style to use when rendering the item in a user interface.
`void`	`initialize(Module module)`	Invokes this item's initializer function, if any, on the given module.
`boolean`	`isAutoFill()`	Gets whether the item value is allowed to be auto-filled.
`boolean`	`isInput()`	Gets whether the item is a module input.
`boolean`	`isOutput()`	Gets whether the item is a module output.
`boolean`	`isPersisted()`	Gets whether to remember the most recent value of the parameter.
`boolean`	`isRequired()`	Gets whether the item value must be specified (i.e., no default).
`T`	`loadValue()`	Deprecated.
`void`	`saveValue(T value)`	Deprecated.
`void`	`setValue(Module module, T value)`	Sets the item's current value with respect to the given module.
`void`	`validate(Module module)`	Invokes this item's validation function, if any, on the given module.
`default String`	`validateMessage(Module module)`	Validates this item's value in the given module, returning any error message rather than throwing.

Methods inherited from interface org.scijava.BasicDetails
get, getDescription, getLabel, is, set, setDescription, setLabel

Methods inherited from interface org.scijava.Named
getName, setName

- Method Detail
  - getInfo
```
ModuleInfo getInfo()
```
    Gets the ModuleInfo to which this item belongs.
  - getType
```
Class<T> getType()
```
    Gets the type of the item.
  - getGenericType
```
Type getGenericType()
```
    Gets the type of the item, including Java generic parameters.
    For many modules, this may be the same Class object returned by getType(), but some module inputs or outputs may be backed by a generic type such as List<String> or Iterable<Integer>.
    
    See Also:
    
    Field.getGenericType()
  - getIOType
```
ItemIO getIOType()
```
    Gets the input/output type of the item.
  - isInput
```
boolean isInput()
```
    Gets whether the item is a module input.
  - isOutput
```
boolean isOutput()
```
    Gets whether the item is a module output.
  - getVisibility
```
ItemVisibility getVisibility()
```
    Gets the visibility of the item.
  - isAutoFill
```
boolean isAutoFill()
```
    Gets whether the item value is allowed to be auto-filled.
  - isRequired
```
boolean isRequired()
```
    Gets whether the item value must be specified (i.e., no default).
  - isPersisted
```
boolean isPersisted()
```
    Gets whether to remember the most recent value of the parameter.
  - getPersistKey
```
String getPersistKey()
```
    Gets the key to use for saving the value persistently.
  - loadValue
```
@Deprecated
T loadValue()
```
    Deprecated.
    
    Loads the item's persisted value. This recalls the value last stored using saveValue(Object).
    Note that this is different than obtaining a module instance's current value for the input; see getValue(Module) for that.
    
    See Also:
    
    ModuleService.load(ModuleItem)
  - saveValue
```
@Deprecated
void saveValue(T value)
```
    Deprecated.
    
    Saves the given value to persistent storage. This allows later restoration of the value via loadValue(), even from a different JVM.
    
    See Also:
    
    ModuleService.save(ModuleItem, Object)
  - getInitializer
```
String getInitializer()
```
    Gets the function that is called to initialize the item's value.
  - initialize
```
void initialize(Module module)
         throws MethodCallException
```
    Invokes this item's initializer function, if any, on the given module.
    
    Throws:
    
    MethodCallException
    
    See Also:
    
    getInitializer()
  - getValidater
```
String getValidater()
```
    Gets the function that is called to validate the item's value.
  - validate
```
void validate(Module module)
       throws MethodCallException
```
    Invokes this item's validation function, if any, on the given module.
    The validation function may signal failure either by throwing an exception or by returning a non-empty String error message.
    
    Throws:
    
    MethodCallException - if validation fails or the method cannot be invoked. When the validater returns a non-empty String, a MethodCallException is thrown with that string as its message.
    
    See Also:
    
    getValidater(), validateMessage(Module)
  - validateMessage
```
default String validateMessage(Module module)
```
    Validates this item's value in the given module, returning any error message rather than throwing.
    The validation function may signal failure either by throwing an exception or by returning a non-empty String error message. This method catches both cases and returns the error message as a string, or null if the value is valid.
    
    Returns:
    
    an error message if the value is invalid, or null if valid.
    
    See Also:
    
    getValidater(), validate(Module)
  - getCallback
```
String getCallback()
```
    Gets the function that is called whenever this item changes.
    This mechanism enables interdependent items of various types. For example, two int parameters "width" and "height" could update each other when another boolean "Preserve aspect ratio" flag is set.
  - callback
```
void callback(Module module)
       throws MethodCallException
```
    Invokes this item's callback function, if any, on the given module.
    
    Throws:
    
    MethodCallException
    
    See Also:
    
    getCallback()
  - getWidgetStyle
```
String getWidgetStyle()
```
    Gets the preferred widget style to use when rendering the item in a user interface.
  - getDefaultValue
```
T getDefaultValue()
```
    Gets the default value.
  - getMinimumValue
```
T getMinimumValue()
```
    Gets the minimum allowed value (if applicable).
  - getMaximumValue
```
T getMaximumValue()
```
    Gets the maximum allowed value (if applicable).
  - getSoftMinimum
```
T getSoftMinimum()
```
    Gets the "soft" minimum value (if applicable).
    The soft minimum is a hint for use in bounded scenarios, such as rendering in a user interface with a slider or scroll bar widget; the parameter value will not actually be clamped to the soft bounds, but they may be used in certain circumstances where appropriate.
  - getSoftMaximum
```
T getSoftMaximum()
```
    Gets the "soft" maximum value (if applicable).
    The soft maximum is a hint for use in bounded scenarios, such as rendering in a user interface with a slider or scroll bar widget; the parameter value will not actually be clamped to the soft bounds, but they may be used in certain circumstances where appropriate.
  - getStepSize
```
Number getStepSize()
```
    Gets the preferred step size to use when rendering the item in a user interface (if applicable).
  - getColumnCount
```
int getColumnCount()
```
    Gets the preferred width of the input field in characters (if applicable).
  - getChoices
```
List<T> getChoices()
```
    Gets the list of possible values.
  - getValue
```
T getValue(Module module)
```
    Gets the item's current value with respect to the given module.
  - setValue
```
void setValue(Module module,
              T value)
```
    Sets the item's current value with respect to the given module.

Interface ModuleItem<T>

Method Summary

Methods inherited from interface org.scijava.BasicDetails

Methods inherited from interface org.scijava.Named

Method Detail

getInfo

getType

getGenericType

getIOType

isInput

isOutput

getVisibility

isAutoFill

isRequired

isPersisted

getPersistKey

loadValue

saveValue

getInitializer

initialize

getValidater

validate

validateMessage

getCallback

callback

getWidgetStyle

getDefaultValue

getMinimumValue

getMaximumValue

getSoftMinimum

getSoftMaximum

getStepSize

getColumnCount

getChoices

getValue

setValue