Spring MongoRepository#findall: ConverterNotFoundException

Spring MongoRepository#findall: ConverterNotFoundException - java

I have two simple documents MyDoc and NestedDoc
MyDoc:
public class MyDoc {
#Id
private final String id;
private final NestedDoc nested;
public MyDoc (MyIdentifier myIdentifier, Nested nested) {
this(myIdentifier.toString(),
new NestedDoc(nested.getIdentifier(), nested.getStp()));
}
#PersistenceConstructor
public MyDoc (String id, NestedDoc nestedDoc) {
this.id = id;
this.nestedDoc = nestedDoc;
}
// ...
}
NestedDoc:
public class NestedDoc {
private final String identifier;
private final Stp stp; // is an enum
#PersistenceConstructor
public NestedDocDoc (String identifier, Stp stp) {
this.identifier = identifier;
this.stp = type;
}
// ...
}
There is a straight forward repository:
public interface MyMongoRepo extends MongoRepository<MyDoc, String> {
default MyDoc findByIdentifier (MyIdentifier identifier) {
return findOne(identifier.toString());
}
}
Now, when I call MyMongoRepo#findAll I get
org.springframework.core.convert.ConverterNotFoundException:
No converter found capable of converting from type [java.lang.String]
to type [com.xmpl.NestedDoc]
Expected Outpout:
When I call MyMongoRepo#findByIdentifier (like in a RestController) I get something like:
{
id: 123,
nested: {
identifier: "abc",
stp: "SOME_CONSTANT",
}
}
and MyMongoRepo#findAll should return an array that contains all known MyDocs.
In addition to the problem, it would be interesting to know why a converter is needed in the first place. What happens under the hood that requires a String to be converted?

You have mongo document in your database which look like below
{
id: 1,
nested: "somevalue"
}
and spring fails to convert String into NestedDoc object.
Fix/Remove the document and you should be fine.

Related

How to deserialize a List of String to a single arg value class?

Basically I always want to unwrap my Id class to the parent object but in case of a List<> I can not use the JsonUnwrapped Annotation from the jackson library.
#lombok.Value
public class Response {
List<MyId> ids;
// ... other fields
}
#lombok.Value
public class MyId {
String id;
}
{
"ids": ["id1", "id2"]
"otherField": {}
}
Working solution with jackson-databind 2.11
#lombok.Value
public class MyId {
#JsonValue
String id;
public MyId(final String id) {
this.id = id;
}
}

You can use #JsonValue. From docs:
Marker annotation that indicates that the value of annotated accessor (either field or "getter" method [a method with non-void return type, no args]) is to be used as the single value to serialize for the instance, instead of the usual method of collecting properties of value. Usually value will be of a simple scalar type (String or Number), but it can be any serializable type (Collection, Map or Bean).
Usage:
#Value
public class MyId {
#JsonValue
String id;
}
Complete code:
public class JacksonExample {
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper objectMapper = new ObjectMapper();
List<MyId> myIds = new ArrayList<>();
MyId id1 = new MyId("one");
MyId id2 = new MyId("two");
myIds.add(id1);
myIds.add(id2);
Response response = new Response(myIds, "some other field value");
System.out.println(objectMapper.writeValueAsString(response));
}
}
#Value
class Response {
List<MyId> ids;
String otherField;
}
#Value
class MyId {
#JsonValue
String id;
}
Output:
{
"ids": [
"one",
"two"
],
"otherField": "some other field value"
}

How to deserialize a Map of Arrays in Simple Framework?

I am trying to deserialize following xml:
<scenario name="test responses">
<cmd name="query1">
<return>success_200.xml</return>
<return>error_500.xml</return>
</cmd>
<cmd name="query2">
<return>success_200.xml</return>
</cmd>
</scenario>
into this class
#Root(name="scenario")
public class TestScenario {
#ElementMap(entry="cmd", key="name", attribute=true, inline=true)
private Map<String,StepsList> scenario;
#Attribute(required = false)
private String name = "";
public static class StepsList {
#ElementList(name="return")
private List<String> steps = new ArrayList<String>();
public List<String> getSteps() {
return steps;
}
}
}
But get a org.simpleframework.xml.core.ValueRequiredException: Unable to satisfy #org.simpleframework.xml.ElementList
How it can be done?

Try this:
#ElementList(required = false, inline = true, name="return")
private List<String> steps = new ArrayList<String>();

So, after couple hours of research, I created a working solution.
Strange enough, but to create a map of arrays you need to use #ElementList decoration with special SimpleFramework utility class Dictionary. Objects inserted into that dictionary must implement Entry interface and can contain any parsing rules. In my case they contain List<String> corresponding to inner <return> tags.
You can read about utility classes in the tutorial: http://simple.sourceforge.net/download/stream/doc/tutorial/tutorial.php#util
#Root(name="scenario")
public class TestScenario {
#ElementList(inline=true)
private Dictionary<StepsList> scenario;
#Attribute(required = false)
private String name = "";
public Dictionary<StepsList> getScenario() {
return scenario;
}
#Root(name="cmd")
public static class StepsList implements Entry {
#Attribute
private String name;
#ElementList(inline=true, entry="return")
private List<String> steps;
#Override
public String getName() {
return name;
}
public List<String> getSteps() {
return steps;
}
}
}
Dictionary is a class implementing java.util.Set, and you can use it like this:
TestScenario test = loadScenario("test.xml");
String step1 = test.getScenario().get("query1").getSteps().get(0);
// step1 is now "success_200.xml"
String step2 = test.getScenario().get("query1").getSteps().get(1);
// step2 is now "error_500.xml"

Referencing a field by its ID instead of expanding it

I am new to the Simple framework for XML (Java) and ran into a problem serializing specific class constructs.
I have two classes:
#Root(name="static")
class StaticData {
#Attribute
private String id;
#Attribute
private String value;
...
}
and
#Root(name="listdata")
class ListData {
// Problem field
#Attribute
private StaticData ref;
#Element
private String name;
}
And receive
"TransformException: Transform of class StaticData not supported".
I want the ref-field in ListData not to expand into the static data XML structure (then #Element would be fine), but to get a reference.
<listdata ref="foo">
<name>bla bla</name>
</listdata>
where "foo" is a valid value for "id" in some StaticData object already loaded in my application.
In JAXB I would use the XmlJavaTypeAdapter annotation
#XmlAttribute(name="id")
#XmlJavaTypeAdapter(MyStaticDataAdapter.class)
but I cannot seem to find a working equivalent in Simple.

In doubt you can use a Converter to implement such a behaviour.
Here's an example:
#Root(name = "listdata")
#Convert(ListData.ListDataConverter.class)
class ListData
{
#Attribute
private StaticData ref;
#Element
private String name;
// ...
// Converter implementation
static class ListDataConverter implements Converter<ListData>
{
#Override
public ListData read(InputNode node) throws Exception
{
/*
* In case you also want to read, implement this too ...
*/
throw new UnsupportedOperationException("Not supported yet.");
}
#Override
public void write(OutputNode node, ListData value) throws Exception
{
node.setAttribute("ref", value.ref.getId());
node.getChild("name").setValue(value.name);
}
}
}
Usage:
Serializer ser = new Persister(new AnnotationStrategy());
/* ^----- important! -----^ */
ListData ld = ...
ser.write(ld, System.out); // Serialize to std out
Output
With these ListData values ...
name = abcdefg
ref = ...
id = 123
value = this is a value
you'll get ...
<listdata ref="123">
<name>def</name>
</listdata>

Jackson enum Serializing and DeSerializer

I'm using JAVA 1.6 and Jackson 1.9.9 I've got an enum
public enum Event {
FORGOT_PASSWORD("forgot password");
private final String value;
private Event(final String description) {
this.value = description;
}
#JsonValue
final String value() {
return this.value;
}
}
I've added a #JsonValue, this seems to do the job it serializes the object into:
{"event":"forgot password"}
but when I try to deserialize I get a
Caused by: org.codehaus.jackson.map.JsonMappingException: Can not construct instance of com.globalrelay.gas.appsjson.authportal.Event from String value 'forgot password': value not one of declared Enum instance names
What am I missing here?

The serializer / deserializer solution pointed out by #xbakesx is an excellent one if you wish to completely decouple your enum class from its JSON representation.
Alternatively, if you prefer a self-contained solution, an implementation based on #JsonCreator and #JsonValue annotations would be more convenient.
So leveraging on the example by #Stanley the following is a complete self-contained solution (Java 6, Jackson 1.9):
public enum DeviceScheduleFormat {
Weekday,
EvenOdd,
Interval;
private static Map<String, DeviceScheduleFormat> namesMap = new HashMap<String, DeviceScheduleFormat>(3);
static {
namesMap.put("weekday", Weekday);
namesMap.put("even-odd", EvenOdd);
namesMap.put("interval", Interval);
}
#JsonCreator
public static DeviceScheduleFormat forValue(String value) {
return namesMap.get(StringUtils.lowerCase(value));
}
#JsonValue
public String toValue() {
for (Entry<String, DeviceScheduleFormat> entry : namesMap.entrySet()) {
if (entry.getValue() == this)
return entry.getKey();
}
return null; // or fail
}
}

Note that as of this commit in June 2015 (Jackson 2.6.2 and above) you can now simply write:
public enum Event {
#JsonProperty("forgot password")
FORGOT_PASSWORD;
}
The behavior is documented here: https://fasterxml.github.io/jackson-annotations/javadoc/2.11/com/fasterxml/jackson/annotation/JsonProperty.html
Starting with Jackson 2.6 this annotation may also be used to change serialization of Enum like so:
public enum MyEnum {
#JsonProperty("theFirstValue") THE_FIRST_VALUE,
#JsonProperty("another_value") ANOTHER_VALUE;
}
as an alternative to using JsonValue annotation.

You should create a static factory method which takes single argument and annotate it with #JsonCreator (available since Jackson 1.2)
#JsonCreator
public static Event forValue(String value) { ... }
Read more about JsonCreator annotation here.

Actual Answer:
The default deserializer for enums uses .name() to deserialize, so it's not using the #JsonValue. So as #OldCurmudgeon pointed out, you'd need to pass in {"event": "FORGOT_PASSWORD"} to match the .name() value.
An other option (assuming you want the write and read json values to be the same)...
More Info:
There is (yet) another way to manage the serialization and deserialization process with Jackson. You can specify these annotations to use your own custom serializer and deserializer:
#JsonSerialize(using = MySerializer.class)
#JsonDeserialize(using = MyDeserializer.class)
public final class MyClass {
...
}
Then you have to write MySerializer and MyDeserializer which look like this:
MySerializer
public final class MySerializer extends JsonSerializer<MyClass>
{
#Override
public void serialize(final MyClass yourClassHere, final JsonGenerator gen, final SerializerProvider serializer) throws IOException, JsonProcessingException
{
// here you'd write data to the stream with gen.write...() methods
}
}
MyDeserializer
public final class MyDeserializer extends org.codehaus.jackson.map.JsonDeserializer<MyClass>
{
#Override
public MyClass deserialize(final JsonParser parser, final DeserializationContext context) throws IOException, JsonProcessingException
{
// then you'd do something like parser.getInt() or whatever to pull data off the parser
return null;
}
}
Last little bit, particularly for doing this to an enum JsonEnum that serializes with the method getYourValue(), your serializer and deserializer might look like this:
public void serialize(final JsonEnum enumValue, final JsonGenerator gen, final SerializerProvider serializer) throws IOException, JsonProcessingException
{
gen.writeString(enumValue.getYourValue());
}
public JsonEnum deserialize(final JsonParser parser, final DeserializationContext context) throws IOException, JsonProcessingException
{
final String jsonValue = parser.getText();
for (final JsonEnum enumValue : JsonEnum.values())
{
if (enumValue.getYourValue().equals(jsonValue))
{
return enumValue;
}
}
return null;
}

I've found a very nice and concise solution, especially useful when you cannot modify enum classes as it was in my case. Then you should provide a custom ObjectMapper with a certain feature enabled. Those features are available since Jackson 1.6. So you only need to write toString() method in your enum.
public class CustomObjectMapper extends ObjectMapper {
#PostConstruct
public void customConfiguration() {
// Uses Enum.toString() for serialization of an Enum
this.enable(WRITE_ENUMS_USING_TO_STRING);
// Uses Enum.toString() for deserialization of an Enum
this.enable(READ_ENUMS_USING_TO_STRING);
}
}
There are more enum-related features available, see here:
https://github.com/FasterXML/jackson-databind/wiki/Serialization-Features
https://github.com/FasterXML/jackson-databind/wiki/Deserialization-Features

Try this.
public enum Event {
FORGOT_PASSWORD("forgot password");
private final String value;
private Event(final String description) {
this.value = description;
}
private Event() {
this.value = this.name();
}
#JsonValue
final String value() {
return this.value;
}
}

I like the accepted answer. However, I would improve it a little (considering that there is now Java higher than version 6 available).
Example:
public enum Operation {
EQUAL("eq"),
NOT_EQUAL("ne"),
LESS_THAN("lt"),
GREATER_THAN("gt");
private final String value;
Operation(String value) {
this.value = value;
}
#JsonValue
public String getValue() {
return value;
}
#JsonCreator
public static Operation forValue(String value) {
return Arrays.stream(Operation.values())
.filter(op -> op.getValue().equals(value))
.findFirst()
.orElseThrow(); // depending on requirements: can be .orElse(null);
}
}

You can customize the deserialization for any attribute.
Declare your deserialize class using the annotationJsonDeserialize (import com.fasterxml.jackson.databind.annotation.JsonDeserialize) for the attribute that will be processed. If this is an Enum:
#JsonDeserialize(using = MyEnumDeserialize.class)
private MyEnum myEnum;
This way your class will be used to deserialize the attribute. This is a full example:
public class MyEnumDeserialize extends JsonDeserializer<MyEnum> {
#Override
public MyEnum deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
JsonNode node = jsonParser.getCodec().readTree(jsonParser);
MyEnum type = null;
try{
if(node.get("attr") != null){
type = MyEnum.get(Long.parseLong(node.get("attr").asText()));
if (type != null) {
return type;
}
}
}catch(Exception e){
type = null;
}
return type;
}
}

Here is another example that uses string values instead of a map.
public enum Operator {
EQUAL(new String[]{"=","==","==="}),
NOT_EQUAL(new String[]{"!=","<>"}),
LESS_THAN(new String[]{"<"}),
LESS_THAN_EQUAL(new String[]{"<="}),
GREATER_THAN(new String[]{">"}),
GREATER_THAN_EQUAL(new String[]{">="}),
EXISTS(new String[]{"not null", "exists"}),
NOT_EXISTS(new String[]{"is null", "not exists"}),
MATCH(new String[]{"match"});
private String[] value;
Operator(String[] value) {
this.value = value;
}
#JsonValue
public String toStringOperator(){
return value[0];
}
#JsonCreator
public static Operator fromStringOperator(String stringOperator) {
if(stringOperator != null) {
for(Operator operator : Operator.values()) {
for(String operatorString : operator.value) {
if (stringOperator.equalsIgnoreCase(operatorString)) {
return operator;
}
}
}
}
return null;
}
}

There are various approaches that you can take to accomplish deserialization of a JSON object to an enum. My favorite style is to make an inner class:
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonFormat;
import com.fasterxml.jackson.annotation.JsonProperty;
import org.hibernate.validator.constraints.NotEmpty;
import java.util.Arrays;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;
import static com.fasterxml.jackson.annotation.JsonFormat.Shape.OBJECT;
#JsonFormat(shape = OBJECT)
public enum FinancialAccountSubAccountType {
MAIN("Main"),
MAIN_DISCOUNT("Main Discount");
private final static Map<String, FinancialAccountSubAccountType> ENUM_NAME_MAP;
static {
ENUM_NAME_MAP = Arrays.stream(FinancialAccountSubAccountType.values())
.collect(Collectors.toMap(
Enum::name,
Function.identity()));
}
private final String displayName;
FinancialAccountSubAccountType(String displayName) {
this.displayName = displayName;
}
#JsonCreator
public static FinancialAccountSubAccountType fromJson(Request request) {
return ENUM_NAME_MAP.get(request.getCode());
}
#JsonProperty("name")
public String getDisplayName() {
return displayName;
}
private static class Request {
#NotEmpty(message = "Financial account sub-account type code is required")
private final String code;
private final String displayName;
#JsonCreator
private Request(#JsonProperty("code") String code,
#JsonProperty("name") String displayName) {
this.code = code;
this.displayName = displayName;
}
public String getCode() {
return code;
}
#JsonProperty("name")
public String getDisplayName() {
return displayName;
}
}
}

In the context of an enum, using #JsonValue now (since 2.0) works for serialization and deserialization.
According to the jackson-annotations javadoc for #JsonValue:
NOTE: when use for Java enums, one additional feature is that value returned by annotated method is also considered to be the value to deserialize from, not just JSON String to serialize as. This is possible since set of Enum values is constant and it is possible to define mapping, but can not be done in general for POJO types; as such, this is not used for POJO deserialization.
So having the Event enum annotated just as above works (for both serialization and deserialization) with jackson 2.0+.

Besides using #JsonSerialize #JsonDeserialize, you can also use SerializationFeature and DeserializationFeature (jackson binding) in the object mapper.
Such as DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE, which give default enum type if the one provided is not defined in the enum class.

In my case, this is what resolved:
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonFormat;
import com.fasterxml.jackson.annotation.JsonProperty;
#JsonFormat(shape = JsonFormat.Shape.OBJECT)
public enum PeriodEnum {
DAILY(1),
WEEKLY(2),
;
private final int id;
PeriodEnum(int id) {
this.id = id;
}
public int getId() {
return id;
}
public String getName() {
return this.name();
}
#JsonCreator
public static PeriodEnum fromJson(#JsonProperty("name") String name) {
return valueOf(name);
}
}
Serializes and deserializes the following json:
{
"id": 2,
"name": "WEEKLY"
}
I hope it helps!

#JsonFormat(shape = JsonFormat.Shape.OBJECT)
public enum LoginOptionType {
PHONE(1, "Phone"), MAIL(2, "mail"), PERSONAL_EMAIL(3, "Personal email");
private static List<LoginOptionType> all;
static {
all = new ArrayList<LoginOptionType>() {
{
add(LoginOptionType.PHONE);
add(LoginOptionType.MAIL);
add(LoginOptionType.PERSONAL_EMAIL);
}
};
}
private final Integer viewValue;
private final String name;
LoginOptionType(Integer viewValue, String name) {
this.viewValue = viewValue;
this.name = name;
}
public Integer getViewValue() {
return viewValue;
}
public String getName() {
return name;
}
public static List<LoginOptionType> getAll() {
return all;
}
}
Response
[
{
"viewValue": 1,
"name": "Phone"
},
{
"viewValue": 2,
"name": "mail"
},
{
"viewValue": 3,
"name": "Personal email"
}
]

Here, 'value' acts as a deserialiser and 'namespace' acts as a serialiser. Hence, you can pass in value "Student Absent" to API while saving, and in DB it will be saved as "STUDENT_ABSENT". On the other hand, while retrieving data in your class, your API will return "Student Absent"
import com.fasterxml.jackson.annotation.JsonProperty;
public enum AttendanceEnums {
STUDENT_PRESENT,
#JsonProperty(value = "Student Absent", namespace = "Student Absent")
STUDENT_ABSENT;
}

I had been looking for a solution to enum serialization and I finally made a solution.
https://github.com/sirgilligan/EnumerationSerialization
https://digerati-illuminatus.blogspot.com/2022/10/java-enum-generic-serializer-and.html
It uses a new annotation and two new classes, EnumerationSerializer and EnumerationDeserializer. You can subclass the EnumerationDeserializer and make a class that sets the enum Class (typical approach) or you can annotate the enum and you don't have to have a subclass of EnumerationDeserializer.
#JsonSerialize(using = EnumerationSerializer.class)
#JsonDeserialize(using = EnumerationDeserializer.class)
#EnumJson(serializeProjection = Projection.NAME, deserializationClass = RGB.class)
enum RGB {
RED,
GREEN,
BLUE
}
Notice how the implementation of ContextualDeserializer pulls the class from the annotation.
https://github.com/sirgilligan/EnumerationSerialization/blob/main/src/main/java/org/example/EnumerationDeserializer.java
There is a lot of good code in this that might give insights.
For your specific question you could do this:
#JsonSerialize(using = EnumerationSerializer.class)
#JsonDeserialize(using = EnumerationDeserializer.class)
#EnumJson(serializeProjection = Projection.NAME, deserializationClass = Event.class)
public enum Event {
FORGOT_PASSWORD("forgot password");
//This annotation is optional because the code looks for value or alias.
#EnumJson(serializeProjection = Projection.VALUE)
private final String value;
private Event(final String description) {
this.value = description;
}
}
Or you could do this:
#JsonSerialize(using = EnumerationSerializer.class)
#JsonDeserialize(using = EnumerationDeserializer.class)
#EnumJson(serializeProjection = Projection.NAME, deserializationClass = Event.class)
public enum Event {
FORGOT_PASSWORD("forgot password");
private final String value;
private Event(final String description) {
this.value = description;
}
}
That's all you have to do.
Then if you have a class that "has a" event you can annotate each occurance to serialize the way you want.
class EventHolder {
#EnumJson(serializeProjection = Projection.NAME)
Event someEvent;
#EnumJson(serializeProjection = Projection.ORDINAL)
Event someOtherEvent;
#EnumJson(serializeProjection = Projection.VALUE)
Event yetAnotherEvent;
}

The simplest way I found is using #JsonFormat.Shape.OBJECT annotation for the enum.
#JsonFormat(shape = JsonFormat.Shape.OBJECT)
public enum MyEnum{
....
}

I did it like this :
// Your JSON
{"event":"forgot password"}
// Your class to map
public class LoggingDto {
#JsonProperty(value = "event")
private FooEnum logType;
}
//Your enum
public enum FooEnum {
DATA_LOG ("Dummy 1"),
DATA2_LOG ("Dummy 2"),
DATA3_LOG ("forgot password"),
DATA4_LOG ("Dummy 4"),
DATA5_LOG ("Dummy 5"),
UNKNOWN ("");
private String fullName;
FooEnum(String fullName) {
this.fullName = fullName;
}
public String getFullName() {
return fullName;
}
#JsonCreator
public static FooEnum getLogTypeFromFullName(String fullName) {
for (FooEnum logType : FooEnum.values()) {
if (logType.fullName.equals(fullName)) {
return logType;
}
}
return UNKNOWN;
}
}
So the value of the property "logType" for class LoggingDto will be DATA3_LOG

This post is old, but if it can help someone, use JsonFormat.Shape.STRING
#JsonFormat(shape = JsonFormat.Shape.STRING)
public enum SomeEnum{
#JsonProperty("SOME_PROPERTY")
someProperty,
...
}
Code results is like this
{"someenum":"SOME_PROPERTY"}

Sourceforge SimpleXML Enum serialization

SimpleXML can serialize a Java Enum fine but when it comes to de-serialization, it returns null instead of creating Enum from the generated XML. Is it something I am doing wrong of Enum serialization is not supported at all?
Serialization returns this:
<TestStatus>
<status>Functional</status>
</TestStatus>
Test Enum:
#Root
public enum TestStatus {
AVAILABLE("Functional"),
NOT_AVAILABLE("Dysfunctional");
#Element
private String status;
private Status(String status) {
this.status = status;
}
public String getStatus() {
return status;
}
}

How do you serialize your enum?
if you use it like this, it should work without problems but will return some different XML:
Example:
#Root
public class Example
{
#Element
private TestStatus status = TestStatus.AVAILABLE;
// ...
}
Test:
final File f = new File("test.xml");
Serializer ser = new Persister();
ser.write(new Example(), f);
Example m = ser.read(Example.class, f);
XML:
<example>
<status>AVAILABLE</status>
</example>
You can rename the xml-tags with annotationarguments, but the value wont be changeable.
Another (possible) solution is using a custom converter:
Annotations of the enum:
#Root()
#Convert(TestStatusConverter.class)
public enum TestStatus
{
// ...
}
Converter (Example)
public class TestStatusConverter implements Converter<TestStatus>
{
#Override
public TestStatus read(InputNode node) throws Exception
{
final String value = node.getNext("status").getValue();
// Decide what enum it is by its value
for( TestStatus ts : TestStatus.values() )
{
if( ts.getStatus().equalsIgnoreCase(value) )
return ts;
}
throw new IllegalArgumentException("No enum available for " + value);
}
#Override
public void write(OutputNode node, TestStatus value) throws Exception
{
// You can customize your xml here (example structure like your xml)
OutputNode child = node.getChild("status");
child.setValue(value.getStatus());
}
}
Test (enum):
final File f = new File("test.xml");
// Note the new Strategy
Serializer ser = new Persister(new AnnotationStrategy());
ser.write(TestStatus.AVAILABLE, f);
TestStatus ts = ser.read(TestStatus.class, f);
System.out.println(ts);
Test (class with enum):
As above but with AnnotationStrategy

You don't need to add annotations to enums, they serialize automatically.

Develop Reference

Java is a programming language and computing platform first released by Sun Microsystems in 1995.

Spring MongoRepository#findall: ConverterNotFoundException - java

You have mongo document in your database which look like below { id: 1, nested: "somevalue" } and spring fails to convert String into NestedDoc object. Fix/Remove the document and you should be fine.

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