Package org.springframework.boot.json

Class JsonWriter.Member<T>

java.lang.Object

org.springframework.boot.json.JsonWriter.Member<T>

Type Parameters:

T - the member type

Enclosing interface:

JsonWriter<T>

public static final class JsonWriter.Member<T>
extends Object

A member that contributes JSON. Typically, a member will contribute a single name/value pair based on an extracted value. They may also contribute more complex JSON structures when configured with one of the using(...) methods.

The when(...) methods may be used to filter a member (omit it entirely from the JSON). The as(Function) method can be used to adapt to a different type.

Method Summary

Modifier and Type	Method	Description
<R> JsonWriter.Member<R>	as(Function<T,R> adapter)	Adapt the value by applying the given Function.
String	toString()
<E, N, V> JsonWriter.Member<T>	usingExtractedPairs(BiConsumer<T,Consumer<E>> elements, Function<E,N> nameExtractor, Function<E,V> valueExtractor)	Add JSON name/value pairs by extracting values from a series of elements.
<E> JsonWriter.Member<T>	usingExtractedPairs(BiConsumer<T,Consumer<E>> elements, JsonWriter.PairExtractor<E> extractor)	Add JSON name/value pairs by extracting values from a series of elements.
JsonWriter.Member<T>	usingMembers(Consumer<JsonWriter.Members<T>> members)	Add JSON based on further JsonWriter.Members configuration.
<N, V> JsonWriter.Member<T>	usingPairs(BiConsumer<T,BiConsumer<N,V>> pairs)	Add JSON name/value pairs.
JsonWriter.Member<T>	when(Predicate<T> predicate)	Only include this member when the given predicate matches.
JsonWriter.Member<T>	whenHasLength()	Only include this member when it is not null and has a toString() that is not zero length.
JsonWriter.Member<T>	whenNot(Predicate<T> predicate)	Only include this member when the given predicate does not match.
JsonWriter.Member<T>	whenNotEmpty()	Only include this member when it is not empty (See ObjectUtils.isEmpty(Object) for details).
JsonWriter.Member<T>	whenNotNull()	Only include this member when its value is not null.
JsonWriter.Member<T>	whenNotNull(Function<T,?> extractor)	Only include this member when an extracted value is not null.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Details

whenNotNull

public JsonWriter.Member<T> whenNotNull()

Only include this member when its value is not null.

Returns:

a JsonWriter.Member which may be configured further

whenNotNull

public JsonWriter.Member<T> whenNotNull(Function<T,?> extractor)

Only include this member when an extracted value is not null.

Parameters:

extractor - an function used to extract the value to test

Returns:

a JsonWriter.Member which may be configured further

whenHasLength

public JsonWriter.Member<T> whenHasLength()

Only include this member when it is not null and has a toString() that is not zero length.

Returns:

a JsonWriter.Member which may be configured further

See Also:

• StringUtils.hasLength(CharSequence)

whenNotEmpty

public JsonWriter.Member<T> whenNotEmpty()

Only include this member when it is not empty (See ObjectUtils.isEmpty(Object) for details).

Returns:

a JsonWriter.Member which may be configured further

whenNot

public JsonWriter.Member<T> whenNot(Predicate<T> predicate)

Only include this member when the given predicate does not match.

Parameters:

predicate - the predicate to test

Returns:

a JsonWriter.Member which may be configured further

when

public JsonWriter.Member<T> when(Predicate<T> predicate)

Only include this member when the given predicate matches.

Parameters:

predicate - the predicate to test

Returns:

a JsonWriter.Member which may be configured further

as

public <R> JsonWriter.Member<R> as(Function<T,R> adapter)

Adapt the value by applying the given Function.

Type Parameters:

R - the result type

Parameters:

adapter - a Function to adapt the value

Returns:

a JsonWriter.Member which may be configured further

usingExtractedPairs

public <E> JsonWriter.Member<T> usingExtractedPairs(BiConsumer<T,Consumer<E>> elements,
 JsonWriter.PairExtractor<E> extractor)

Add JSON name/value pairs by extracting values from a series of elements. Typically used with a Iterable.forEach(Consumer) call, for example:

 members.add(Event::getTags).usingExtractedPairs(Iterable::forEach, pairExtractor);
 

When used with a named member, the pairs will be added as a new JSON value object:

 {
   "name": {
     "p1": 1,
     "p2": 2
   }
 }
 

When used with an unnamed member the pairs will be added to the existing JSON object:

 {
   "p1": 1,
   "p2": 2
 }
 

Type Parameters:

E - the element type

Parameters:

elements - callback used to provide the elements

extractor - a JsonWriter.PairExtractor used to extract the name/value pair

Returns:

a JsonWriter.Member which may be configured further

See Also:

• usingExtractedPairs(BiConsumer, Function, Function)
• usingPairs(BiConsumer)

usingExtractedPairs

public <E,
N,
V> JsonWriter.Member<T> usingExtractedPairs(BiConsumer<T,Consumer<E>> elements,
 Function<E,N> nameExtractor,
 Function<E,V> valueExtractor)

Add JSON name/value pairs by extracting values from a series of elements. Typically used with a Iterable.forEach(Consumer) call, for example:

 members.add(Event::getTags).usingExtractedPairs(Iterable::forEach, Tag::getName, Tag::getValue);
 

When used with a named member, the pairs will be added as a new JSON value object:

 {
   "name": {
     "p1": 1,
     "p2": 2
   }
 }
 

When used with an unnamed member the pairs will be added to the existing JSON object:

 {
   "p1": 1,
   "p2": 2
 }
 

Type Parameters:

E - the element type

N - the name type

V - the value type

Parameters:

elements - callback used to provide the elements

nameExtractor - Function used to extract the name

valueExtractor - Function used to extract the value

Returns:

a JsonWriter.Member which may be configured further

See Also:

• usingExtractedPairs(BiConsumer, PairExtractor)
• usingPairs(BiConsumer)

usingPairs

public <N,
V> JsonWriter.Member<T> usingPairs(BiConsumer<T,BiConsumer<N,V>> pairs)

Add JSON name/value pairs. Typically used with a Map.forEach(BiConsumer) call, for example:

 members.add(Event::getLabels).usingPairs(Map::forEach);
 

When used with a named member, the pairs will be added as a new JSON value object:

 {
   "name": {
     "p1": 1,
     "p2": 2
   }
 }
 

When used with an unnamed member the pairs will be added to the existing JSON object:

 {
   "p1": 1,
   "p2": 2
 }
 

Type Parameters:

N - the name type

V - the value type

Parameters:

pairs - callback used to provide the pairs

Returns:

a JsonWriter.Member which may be configured further

See Also:

• usingExtractedPairs(BiConsumer, PairExtractor)
• usingPairs(BiConsumer)

usingMembers

public JsonWriter.Member<T> usingMembers(Consumer<JsonWriter.Members<T>> members)

Add JSON based on further JsonWriter.Members configuration. For example:

 members.add(User::getName).usingMembers((personMembers) -> {
     personMembers.add("first", Name::first);
     personMembers.add("last", Name::last);
 });
 

When used with a named member, the result will be added as a new JSON value object:

 {
   "name": {
     "first": "Jane",
     "last": "Doe"
   }
 }
 

When used with an unnamed member the result will be added to the existing JSON object:

 {
   "first": "John",
   "last": "Doe"
 }
 

Parameters:

members - callback to configure the members

Returns:

a JsonWriter.Member which may be configured further

See Also:

• usingExtractedPairs(BiConsumer, PairExtractor)
• usingPairs(BiConsumer)

toString

public String toString()

Overrides:

toString in class Object