i do not understand why an Entity no argument constructor is being called when providing a request body? if i delete it and the only constructor that exist is the one that receive arguments, i get the expected output print, but i must implement a no argument constructor in order to save the Entity in the database.
this is the request body:
{
"str": "stringgg",
"intt": 2,
"doublee": 1.003
}
this is the route: when commenting out the empty constructor, the values of the new instance match the request json body
#PostMapping("/save")
public List<Modell> obj(#RequestBody Modell model) {
modelRepository.save(model);
System.out.println(model.toString());
return modelRepository.findAll();
}
this is the entity class:
#Table(name = "modelltbl")
#Entity
public class Modell {
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE)
#Column(name = "id", nullable = false)
private long id;
#Column(name = "str", nullable = true)
private String str;
#Column(name = "intt", nullable = true)
private int intt;
#Column(name = "doublee", nullable = true)
private double doublee;
public Modell(String str, int intt, double doublee)
{
this.str = str;
this.intt = intt;
this.doublee = doublee;
}
public Modell(){}
#Override
public String toString()
{
return String.format("model class,params: %s , %o , %f ", str , intt, doublee);
}
}
First of all: Do not use entities iat controller level. It is bad application Design.
The json will be converted throug jackson library which creates the object by calling the default constructor and the setter of the properties. If you do not want this behavior you can use the #JsonCreator annotation.
#JsonCreator
public Modell(#JsonProperty("str")String str, #JsonProperty("intt")int intt, #JsonProperty("doublee")double doublee)
{
this.str = str;
this.intt = intt;
this.doublee = doublee;
}
Related
I want to allow to sort by every field in the class, without having to write switch/ if statements.
My idea was to find the Field that matches given string value by name and then, with Stream API neatly sort. IntelliJ screamed that i need to surround it with try-catch, so it is not so neatly looking, but that's not important, as it does not work.
private List<MyEntity> getSorted(List<MyEntity> list, SearchCriteria criteria) {
Field sortByField = findFieldInListByName(getFieldList(MyEntity.class), criteria.getSortBy());
return list.stream().sorted(Comparator.comparing(entity-> {
try {
return (MyEntity) sortByField.get(entity);
} catch (IllegalAccessException e) {
e.printStackTrace();
}
return entity;
})).collect(Collectors.toList());
}
In the MyEntity class I have added Comparable interface, but I am not sure what should be in the body of Compare(), as I dont want to specify how to compare objects, because it will change based on the selected sorting.
EDIT: Added Entity below:
#Data
#Entity
#Table(name = "role_management", schema = "mdr")
#Builder
#NoArgsConstructor
#AllArgsConstructor
#EqualsAndHashCode
public class MyEntity implements Comparable{
#Id
#Column(name = "uuid", unique = true, insertable = false, updatable = false)
#GeneratedValue(strategy = GenerationType.AUTO)
private UUID uuid;
#ManyToOne
#JoinColumn(name = "user_id", nullable = false)
private UserEntity user;
#Basic
#NonNull
#Column(name = "role")
private String role;
#Basic
#Column(name = "action")
#Enumerated(EnumType.STRING)
private RoleAction action;
#Basic
#Column(name = "goal")
#Enumerated(EnumType.STRING)
private RoleGoal goal;
#Column(name = "date")
private LocalDateTime date;
#OneToOne(cascade = CascadeType.ALL)
#JoinColumn(name = "reporter_id", referencedColumnName = "uuid")
private UserEntity reporter;
#OneToOne(cascade = CascadeType.ALL)
#JoinColumn(name = "authorizer_id", referencedColumnName = "uuid")
private UserEntity authorizer;
#Basic
#Column(name = "ezd")
private String ezd;
#Basic
#Column(name = "is_last")
private boolean isMostRecent;
#Override
public int compareTo(Object o) {
return 0;
}
}
EDIT 2: My code based on the #Sweeper solution:
UserEntity (nullable)
#Override
public int compareTo(UserEntity other) {
if (other == null) {
return 1;
}
return this.getMail().compareTo(other.getMail());
}
Comparator:
public static Comparator getSortComparator(Field sortByField) {
return Comparator.nullsLast(Comparator.comparing(entity -> {
try {
Object fieldValue = sortByField.get(entity);
if (!(fieldValue instanceof Comparable<?>) && fieldValue != null) {
throw new IllegalArgumentException("...");
}
return (Comparable) fieldValue;
} catch (IllegalAccessException e) {
throw new MdrCommonException(e.getLocalizedMessage());
}
}));
}
MyEntity should not implement Comparable. It is the fields, by which you are going to sort the list of MyEntity objects, that needs to be Comparable. For example, if you are sorting by the field user, which is a UserEntity, then UserEntity is the thing that needs to be comparable, not MyEntity.
The lambda's job should just be to check that the fields are indeed Comparable, and throw an exception if they are not.
Since you don't know the types of the fields at compile time, however, you'd have to use a raw type here. The comparing call would look like this:
Comparator.comparing(entity -> {
try {
Object fieldValue = sortByField.get(entity);
// This check still passes if the type of fieldValue implements Comparable<U>,
// where U is an unrelated type from the type of fieldValue, but this is the
// best we can do here, since we don't know the type of field at compile time
if (!(fieldValue instanceof Comparable<?>) && fieldValue != null) {
throw new IllegalArgumentException("Field is not comparable!");
}
return (Comparable)fieldValue;
} catch (IllegalAccessException e) {
throw new RuntimeException(e);
}
})
You can create automatically comparators for any field of any class using reflection but is better create specific comparators (will be typechecked).
Your entity is a normal class with normal fields then, the usual Java sorting machinery should do the job:
Basically, if you define one comparator for every field (even deep fields into your entity):
public final static Comparator<MyEntity> ByField1 = comparing(MyEntity::getField1);
public final static Comparator<MyEntity> ByField2 = comparing(MyEntity::getField2);
public final static Comparator<MyEntity> ByField3 = comparing(MyEntity::getField3);
public final static Comparator<MyEntity> ByDeep1 = comparing(a -> a.getField4().getDeep1());
public final static Comparator<MyEntity> ByDeep2 = comparing(a -> a.getField4().getDeep2());
public final static Comparator<MyEntity> ByDeep3 = comparing(a -> a.getField4().getDeep3());
You can sort using complex sorting expressions:
data.stream()
.sorted(ByField2.reversed().thenComparing(ByDeep2))
.forEach(System.out::println);
a full example could be
public static void main(String[] args) {
List<MyEntity> data =
Stream.of("Row1", "Row2").flatMap(field1 ->
Stream.of(101, 102).flatMap(field2 ->
Stream.of(true, false).flatMap(field3 ->
Stream.of("Row1", "Row2").flatMap(deep1 ->
Stream.of(101, 102).flatMap(deep2 ->
Stream.of(true, false).map(deep3 ->
new MyEntity(field1, field2, field3, new MyDeepField(deep1, deep2, deep3))))))))
.collect(toList());
data.stream()
.sorted(ByField2.reversed().thenComparing(ByDeep2))
.forEach(System.out::println);
}
#Getter
#Setter
#AllArgsConstructor
static class MyDeepField {
private String deep1;
private Integer deep2;
private Boolean deep3;
}
#Getter
#Setter
#AllArgsConstructor
static class MyEntity {
private String field1;
private Integer field2;
private Boolean field3;
private MyDeepField field4;
public final static Comparator<MyEntity> ByField1 = comparing(MyEntity::getField1);
public final static Comparator<MyEntity> ByField2 = comparing(MyEntity::getField2);
public final static Comparator<MyEntity> ByField3 = comparing(MyEntity::getField3);
public final static Comparator<MyEntity> ByDeep1 = comparing(a -> a.getField4().getDeep1());
public final static Comparator<MyEntity> ByDeep2 = comparing(a -> a.getField4().getDeep2());
public final static Comparator<MyEntity> ByDeep3 = comparing(a -> a.getField4().getDeep3());
#Override
public String toString() {
return "MyEntity{" +
"field1='" + field1 + '\'' +
", field2=" + field2 +
", field3=" + field3 +
", deep1=" + field4.getDeep1() +
", deep2=" + field4.getDeep2() +
", deep3=" + field4.getDeep3() +
'}';
}
}
with output
MyEntity{field1='Row1', field2=102, field3=true, deep1=Row1, deep2=101, deep3=true}
MyEntity{field1='Row1', field2=102, field3=true, deep1=Row1, deep2=101, deep3=false}
...
MyEntity{field1='Row2', field2=101, field3=false, deep1=Row2, deep2=102, deep3=true}
MyEntity{field1='Row2', field2=101, field3=false, deep1=Row2, deep2=102, deep3=false}
The criteria field into your SearchCriteria class is some field of type Comparator<MyEntity> or a mapping using an enumeration or parsing string expressions or so...
I'm creating eCommerce for merchants using spring boot with JPA.
I have an issue while creating the order service.
I want to only pass the ID of the nested objects in the request body instead of sending the full nest objects because the size will be extremely big.
Here is my code.
Merchant can do many orders
Order
#Entity
#Table(name = "Orders")
#XmlRootElement
#JsonIgnoreProperties({"hibernateLazyInitializer", "handler"})
public class Order extends BasicModelWithIDInt {
#Basic(optional = false)
#Column(name = "Quantity")
private Integer quantity;
#Basic(optional = false)
#Size(min = 1, max = 150)
#Column(name = "Notes")
private String notes;
#JoinColumn(name = "ProductID", referencedColumnName = "ID")
#ManyToOne(optional = false, fetch = FetchType.LAZY)
#JsonIgnoreProperties
private Product productID;
#JoinColumn(name = "MerchantID", referencedColumnName = "ID")
#ManyToOne(optional = false, fetch = FetchType.LAZY)
private Merchent merchent;
#JoinColumn(name = "OrderSatusID", referencedColumnName = "ID")
#ManyToOne(optional = false, fetch = FetchType.EAGER)
private OrderStatus orderStatus;
// Getters and Setters
}
Order Holder
public class OrderHolder {
#NotNull
private Order order;
public Order getOrder() {
return order;
}
public void setOrder(Order order) {
this.order = order;
}
}
OrderRepo
public interface OrderRepo extends JpaRepository<Order, Integer> {
}
Order Controller
#RestController
#RequestMapping(value = "order", produces = MediaType.APPLICATION_JSON_VALUE)
public class OrderRestController extends BasicController<OrderHolder>{
#Autowired
private OrderRepo orderRepo;
#PostMapping("create")
public ResponseEntity<?> create(#RequestBody #Valid OrderHolder orderHolder, Principal principal) throws GeneralException {
log.debug( "create order {} requested", orderHolder.toString());
Order order = new Order();
order = orderHolder.getOrder();
System.out.println("###############"+order);
try {
order = orderRepo.save(order);
log.info( "Order {} has been created", order );
} catch (Exception e) {
log.error( "Error creating Order: ", e );
e.printStackTrace();
throw new GeneralException( Errors.ORDER_CREATION_FAILURE, e.toString() );
}
return ResponseEntity.ok( order );
}
}
I need request body to look like the below instead of including the full Merchant and Product objects inside the request.
You can make use of JsonView to return only id of product and merchant
public class OrderView {}
...
public class Product{
#Id
#JsonView(OrderView.class)
private Integer id
private String otherFieldWithoutJsonView
...
}
and then in your controller
#PostMapping("create")
#JsonView(OrderView.class) // this will return the product object with one field (id)
public ResponseEntity<?> create(#RequestBody #Valid OrderHolder orderHolder, Principal principal) throws GeneralException {
...
}
hope this can help you
Just have a separate contract class.
public class OrderContract {
private int merchantID;
private String notes;
....
//getter, setters
}
public class OrderHolder {
#NotNull
private OrderContract orderContract;
public OrderContract getOrderContract() {
return orderContract;
}
public void setOrder(OrderContract orderContract) {
this.orderContract = orderContract;
}
}
And before making a call to the Repository , translate from OrderContract to Order.
I would like to share something regarding this.
I have searched a lot on internet and tried lot of things, but the solution given here suited well for this scenario.
https://www.baeldung.com/jackson-deserialization
You need to create a Custom-deserializer for your model by extending StdDeserializer from com.fasterxml.jackson.databind.deser.std.StdDeserializer, where you just want to pass id's and not the whole object in the request.
I have given below example for User Model with Address object.
User(long userId, String name, Address addressId)
Address(long addressId, String wholeAddress)
Writing Deserializer for User class
public class UserDeserializer extends StdDeserializer<User> {
public User() {
this(null);
}
public User Deserializer(Class<?> vc) {
super(vc);
}
#Override
public User deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JacksonException {
JsonNode node = p.getCodec().readTree(p);
long id = 0;
long addressId = (Long) ((IntNode) node.get("addressId")).numberValue().longValue();
return new User(id, name, new Address(addressId, null)
}
Now you have to use
#JsonDeserialize(using = UserDeserializer.class)
public Class User {
...
}
POST request
Before custom deserialization
{
"name" : "Ravi",
"addressId" : { "id" : 1}
}
After custom Deserialization
{
"name" : "Ravi",
"addressId" : 1
}
Also while GET /user/:id call you will get the whole obj like
{
"name" : "Ravi",
"addressId" : { "id" : 1, "wholeAddress" : "Some address"}
}
I'm working on a Spring Boot 2.0.5.RELEASE project.
I have a field in an Oracle database declared as CHAR(1) with a JPA converter as follows:
public class CharToBooleanConverter implements AttributeConverter<String, Boolean> {
#Override
public Boolean convertToDatabaseColumn(String s) {
return s.equalsIgnoreCase("t");
}
#Override
public String convertToEntityAttribute(Boolean aBoolean) {
if(aBoolean.equals(true)){
return "t";
} else {
return "f";
}
}
}
This converter is used in my StructureElement class twice:
#Entity
#Table(name = "OBS_STRUCTURE_ELEMENT2")
#SequenceGenerator(name = "structure_element_seq", sequenceName = "structure_element_seq", allocationSize = 1)
public class StructureElement {
#Id
#Column(name = "NO_ELEMENT")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "structure_element_seq")
private long id;
#Column(name = "TAG")
private String tag;
#Column(name = "DESCRIPTION")
private String description;
#Column(name = "SUITE")
private int sequence;
#Column(name = "OPTIONNEL")
#Convert(converter = CharToBooleanConverter.class)
private boolean optional;
#Column(name = "REPETITIF")
#Convert(converter = CharToBooleanConverter.class)
private boolean repetitive;
#ManyToOne
#JoinColumn(name = "NOM_STRUCTURE_TYPE")
private Structure typeStructure;
#Embedded
private PersistenceSignature signature;
}
The problem is that when I try to send a Structure through a RestController I receive the following in console:
Resolved [org.springframework.http.converter.HttpMessageNotWritableException: Could not write JSON: Could not set field value [t] value by reflection : [class be.solodoukhin.domain.StructureElement.optional] setter of be.solodoukhin.domain.StructureElement.optional; nested exception is com.fasterxml.jackson.databind.JsonMappingException: Could not set field value [t] value by reflection : [class be.solodoukhin.domain.StructureElement.optional] setter of be.solodoukhin.domain.StructureElement.optional (through reference chain: be.solodoukhin.domain.Structure["elements"])]
With an 500 Internal Server Error response.
Here is my method:
#RestController
#RequestMapping("/structure")
public class StructuresController {
#GetMapping("/{name}")
public ResponseEntity<Structure> getOne(#PathVariable("name") String name)
{
LOGGER.info("Call to StructuresController.getOne with name = " + name);
Optional<Structure> found = this.structureRepository.findById(name);
if(found.isPresent()){
return ResponseEntity.ok(found.get());
}
else
{
return ResponseEntity.badRequest().body(null);
}
}
}
I've tried to use hibernate specific annotation #Type(type = "true_false"). It works but this produces an uppercase T or F in the database.
I've tried to write a JSON serializer that extends com.fasterxml.jackson.databind.ser.std.StdSerializer using this link without success.
Isn't your converter the wrong way round? Your convertToDatabaseColumn has it going from a String to a Boolean. Surely you want it going from Boolean to String. And the convertToEntityAttribute going from String to Boolean.
I suspect that the convert is returning a value of "t" or "f" which can't then be put into the boolean field in the entity.
I think it should be...
public class CharToBooleanConverter implements AttributeConverter<Boolean, String> {
#Override
public Boolean convertToEntityAttribute(String s) {
return s != null && s.equalsIgnoreCase("t");
}
#Override
public String convertToDatabaseColumn(Boolean aBoolean) {
return (aBoolean != null && aBoolean) ? "t" : "f";
}
}
I am pretty new to java development but I have developed couple of production ready applications on PHP and Python. I am developing a REST api using spring boot framework and find it little confusion in terms to handling/parsing the request body. In the other languages I have worked on, it was much simpler.
If its in python/php, I need not define all the parameters of the request explicitly to handle the request body. But in java, I have to predefine all the request parameters in a POJO class and MAP it. So for every API endpoint I make, I will have to define all in a Java class as the data layer.
But in other languages, I dont need to map anything to an array, in php $_POST holds the data objects.
My question is
I have the following requests
1.
{
"category": "product/invoice/event",
"item_id": "Unique tool identifier id",
"platforms_id": "1",
"share_platform_settings": {
"fb_share_type": "page/profile",
"fb_share_name": "profilename/pagename",
"fb_id": "fb_uid/page_id"
}
}
2.
{
"category": "product/invoice/event",
"item_id": "Unique tool identifier id",
"platforms_id": "1",
"share_platform_settings": {
"twitter_username": "page/profile",
"twitter_user_access_token": "profilename/pagename"
}
}
I had written a class
import com.google.common.base.Objects;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
#Entity
public class User {
#Id
#NotNull
#Size(max = 64)
#Column(name = "id", nullable = false, updatable = false)
private String id;
private String category;
private String item_id;
private String platforms_id;
private String fb_share_type;
private String fb_share_name;
private String fb_id;
User() {
}
public User(final String id, final String category,final String item_id,final String platforms_id,final String fb_share_type,final String fb_share_name,final String fb_id) {
this.id = id;
this.category = category;
this.item_id = item_id;
this.platforms_id = platforms_id;
this.fb_share_type = fb_share_type;
this.fb_share_name = fb_share_name;
this.fb_id = fb_id;
}
public String getId() {
return id;
}
public String getCategory() {
return category;
}
public String getItemId() {
return item_id;
}
public String getFbShareType() {
return platforms_id;
}
public String getFbShareName() {
return category;
}
public String getFbId() {
return category;
}
public String setCategory(String category) {
return this.category = category;
}
public void setId(String id) {
this.id = id;
}
public void setItemId(String item_id) {
this.item_id = item_id;
}
public void setFbShareType(String fb_share_type) {
this.fb_share_type = fb_share_type;
}
public void setFbShareName(String fb_share_name) {
this.fb_share_name = fb_share_name;
}
public void setFbId(String fb_id) {
this.fb_id = fb_id;
}
#Override
public String toString() {
return Objects.toStringHelper(this)
.add("id", id)
.add("item_id", item_id)
.add("fb_share_type", fb_share_type)
.add("fb_share_name", fb_share_name)
.add("fb_id", fb_id)
.add("category", category)
.toString();
}
}
I can map the request to the class using #RequestBody Request request,
but I have define the class Request with my request params. But my request params keeps changing, I have a different json request structure 2. What would I do in that case? What if if I have n number of different requests on the same API? Do I need to create classes for each of them? or define all the variables in this class itself? Or is there anyway, I dont need anyclass, is jackson dependency used for that?
Sorry if this a dump question, I am pretty new to java development and I really appreciate understanding a question like this :P
As you are using key/value parameters in your JSON, you will need to map it with a similar structure in the Backend so you will need to use a collection of type Map like Map<String, String> share_platform_settings in your Entity.
And your Entity will be like:
#Entity
public class User {
#Id
#NotNull
#Size(max = 64)
#Column(name = "id", nullable = false, updatable = false)
private String id;
private String category;
private String item_id;
private String platforms_id;
private Map<String, String> share_platform_settings;
//Constructors, getters and setters
}
This should work for you.
I am using Stripes for a project and have a situation I cannot understand. In my action bean I have a list of objects (for setting app config params) and in the jsp I am dynamically creating input fields for each object. For a normal edit everything works fine however if I try and set a field to empty the object value remains what it was previously. I have looked extensively through the code and am confident it is not being done by any of the code we have written. When I debug I can see that the setValue() method of my object is being called for all configuration objects except the one that is blank, rather than setValue being called with an empty string which is what I would expect.
Does anyone know if Stripes is doing something under the hood which is affecting this?
Thanks
Snippets of Code:
Object code:
public class Configuration implements Serializable {
#Id
#Basic(optional = false)
#Column(name = "id", nullable = false)
private Integer id;
#Basic(optional = false)
#Column(name = "name", nullable = false, length = 100, updatable = false)
private String name;
#Basic(optional = true)
#Column(name = "value", nullable = true, length = 200)
private String value;
...
public void setValue(String value) {
//This is never called when I empty my input field
this.value = value;
}
...
}
Action Bean Code:
public class ConfigActionBean extends BaseActionBean {
private List<Configuration> allConfigurationEntries;
#Before(stages = LifecycleStage.BindingAndValidation)
public void rehydrate() {
allConfigurationEntries = configurationService.getAllEntries();
}
#DefaultHandler
public Resolution view() {
return new ForwardResolution(
"/WEB-INF/jsp/admin/configuration.jsp");
}
public Resolution Save() {
configurationService.saveAllEntries(allConfigurationEntries,is);
return new RedirectResolution(ConfigActionBean.class,"view");
}
public void setAllConfigurationEntries(
List<Configuration> allConfigurationEntries) {
this.allConfigurationEntries = allConfigurationEntries;
}
public List<Configuration> getAllConfigurationEntries() {
return allConfigurationEntries;
}
...
}
View JSP Code:
...
<c:forEach items="${actionBean.allConfigurationEntries}" var="items" varStatus="loop">
<div>
<s:label for="allConfigurationEntries[${loop.index}].value">${items.name}</s:label>
<s:text id="${items.name}" name="allConfigurationEntries[${loop.index}].value" value="${items.value}" />
</div>
</c:forEach>
...
Webbrowsers don't add empty fields to the http request. Thus by removing the #Before method and putting this code into the view() method you're issue will be resolved.