Lens (json-values 8.0.0-RC3 API)

java.lang.Object
- jsonvalues.Lens<S,O>

Type Parameters:

S - the source of a lens

O - the target of a lens

Direct Known Subclasses:

JsArrayLens, JsBigIntLens, JsBoolLens, JsDecimalLens, JsDoubleLens, JsIntLens, JsLongLens, JsObjLens, JsPathPairLens, JsStrLens, JsValueLens, JsValuePairLens
```
public class Lens<S,O>
extends Object
```
A Lens is an optic that can be seen as a pair of functions: - get: S => O i.e. from an S, we can extract an O - set: (O, S) => S i.e. from an S and a O, we obtain a S. Unless a prism, to go back to S we need another S. Typically a Lens can be defined between a Product (e.g. record, tuple) and one of its component. Given a lens there are essentially three things you might want to do: -view the subpart -modify the whole by changing the subpart -combine this lens with another lens to look even deeper

Field Summary

Fields
Modifier and Type	Field	Description
`Function<S,O>`	`get`	function to view the part
`Function<Function<O,O>,Function<S,S>>`	`modify`	function to modify the whole by modifying the subpart with a function
`Function<O,Function<S,S>>`	`set`	function to modify the whole by setting the subpart

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`<A> Function<S,A>`	`compose(Lens<O,A> other)`
`Predicate<S>`	`exists(Predicate<O> predicate)`	check if there is a target and it satisfies the predicate
`Function<S,Optional<O>>`	`find(Predicate<O> predicate)`	find if the target satisfies the predicate

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - get
```
public final Function<S,O> get
```
    function to view the part
  - set
```
public final Function<O,Function<S,S>> set
```
    function to modify the whole by setting the subpart
  - modify
```
public final Function<Function<O,O>,Function<S,S>> modify
```
    function to modify the whole by modifying the subpart with a function
- Method Detail
  - find
```
public Function<S,Optional<O>> find(Predicate<O> predicate)
```
    find if the target satisfies the predicate
    
    Parameters:
    
    predicate - the predicate
    
    Returns:
    
    a function from the whole to an optional subpart
  - compose
```
public <A> Function<S,A> compose(Lens<O,A> other)
```
  - exists
```
public Predicate<S> exists(Predicate<O> predicate)
```
    check if there is a target and it satisfies the predicate
    
    Parameters:
    
    predicate - the predicate
    
    Returns:
    
    a predicate on the whole