I have an entity. Some times the inner collection of info elements not get created. So to implementing correspond method I need null checking.
public class Tag {
...
private Set<ProjectInfo> projectInfoSet;
...
public void addProjectInfo(ProjectInfo projectInfo) {
if (this.projectInfoSet == null) {
this.projectInfoSet = new HashSet<>();
}
this.projectInfoSet.add(projectInfo);
}
}
I believe Java8 provides better solution. For example using Optional class. But i'm not sure if it is good to use Optional in my entity class. Other case possible I do not need here optional, because I need to create projectInfoSet, it should like behavioral pattern strategy.
Can someone recommend the better implementation way or explanations how it could be done in better way.
If you are using jackson you can use a configuration parameter to initialiase it ?
Like this here
ObjectMapper mapper = new ObjectMapper();
mapper.getSerializationConfig().setSerializationInclusion(Inclusion.NON_DEFAULT);
Add initial value to your field and forget about null-check:
public class Tag {
...
private Set<ProjectInfo> projectInfoSet = new HashSet<>();
...
public void addProjectInfo(ProjectInfo projectInfo) {
this.projectInfoSet.add(projectInfo);
}
}
Related
I would like a custom entity listener to generate an auto-incremented alias for a few of the entities.
I have implemented one util class in order to generate auto incremented alias for the entities in a distributed environment as follows:
#Component
public class AutoIncrementingIdGenerationUtil {
private final RedisTemplate<String, Object> redisTemplate;
public AutoIncrementingIdGenerationUtil(
RedisTemplate<String, Object> redisTemplate) {
this.redisTemplate = redisTemplate;
}
public String getNextSequenceNumber(String keyName) {
RedisAtomicLong counter = new RedisAtomicLong(keyName,
Objects.requireNonNull(redisTemplate.getConnectionFactory()));
return counter.incrementAndGet();
}
}
Now, I have several entities in my application, for a FEW OF ENTITIES, I would like to generate the alias.
So I am writing my own custom entity listener as follows:
#Component
public class CustomEntityListener<T> {
private final AutoIncrementingIdGenerationUtil autoIncrementingIdGenerationUtil;
public CustomEntityListener(
AutoIncrementingIdGenerationUtil autoIncrementingIdGenerationUtil) {
this.autoIncrementingIdGenerationUtil = autoIncrementingIdGenerationUtil;
}
#PrePersist
void onPrePersist(Object entity) { <----HERE I WOULD LIKE TO CAST TO CONCRETE ENTITY TYPE,
if(StringUtils.isBlank(entity.getAlias())) {
entity.setAlias(autoIncrementingIdgenerationUtil.getNextSequenceNumber(entity.getEntityType());
}
}
As mentioned above, all of the entities do not have an alias attribute. I am not getting any proper idea regarding how to do this. One bad idea is to use getTEntityype(). But in this case, it would be too many if-else and typecast accordingly, which will not look good. Any better idea regarding how to do it?
Another related question in the same context, if I have an entity having a #PrePersist function already, will the function defined in entity listener override this, OR will both of them run?
Entity listeners cannot be parameterized. Just make the relevant entities implement an interface, e.g. Aliased, with a setAlias() method. You'll then have a single type to cast to.
Also, why use Redis? Doesn't your DB have sequences?
In a Mapstruct interface, how can I convert an id to a Set< UserSystem > ?
I tried as follows but unsuccessfully because error occurs:
#Mapper(componentModel = "spring", uses = {UserSystemService.class})
public interface CompanyPostMapper extends EntityMapper<CompanyPostDTO, Company> {
#Mapping(source = "userSystemId", target = "userSystems", expression = "java(userSystemService.findByIdAndAddToSet(id))")
Company toEntity(CompanyPostDTO dto);
default Company fromId(Long id) {
if (id == null) {
return null;
}
Company company = new Company();
company.setId(id);
return company;
}
}
I don't know if I understood the use of the "uses" parameter correctly, but basically I would like to get the ID and query the register and return a Set with the register.
I was going to try "qualifiedByName" and create a method in the Mapper interface, but I don't know how I can inject the Repository and I don't know if that would be a good practice.
What would be the best way to solve?
MapStruct is a mapping framework. You are doing a lookup inside the mapping. It is possible of course (look at the JPA mapping example where an #Context is used). But you can't inherit EntityMapper<CompanyPostDTO, Company> at the same time.
Normally, you need to take the lookup outside your mapping logic and use an update method to update the object.
Your mapping would then look like:
#Mapper(componentModel = "spring" )
public interface CompanyPostMapper {
void updateEntity(CompanyPostDTO dto, #MappingTarget Company entity);
}
// and your call would look like:
public class CallingService{
Company company = userSystemService.findByIdAndAddToSet(id));
if (company == null) {
company = new Company();
}
companyPostMapper.updateEntity(dto, company);
}
Since I want to use ObservableLists in my entities classes within JavaFX, originally I had a problem with the dedicated List implementation and injection over reflection that Hibernate is using by default. Therefore I decided to have my Entity classes annotated with #Access(AccessType.PROPERTY), because I want to enforce that Hibernate uses my getter and setter methods and not reflection.
In a particular class I have a number of List attributes e.g. protected List<CostEstimate> costEstimates;. For each of these lists I have getters and setters which are annotated accordingly. So far so good, that seems to work.
The trouble is that in my UI I don't want to show e.g. all costEstimates that were created over time, but only the last one. So I created a method public CostEstimate getLastCostEstimate() which would return only the last element from the List. This method is annotated with #Transient since there is no matching column in the MySQL database, since it only returns the last element from the related list.
My controller class binds getLastCostEstimate() of the entity to the according UI element.
In the default constructor of my entity class the costEstimates list is initialized with a initial default estimate, such that getLastCostEstimate() should always return a meaningful CostEstimate. In the debugger I can see that this initialization is executed. However, at run time the costEstimates list is empty and I get an IndexOutOfBoundsException. I assume that has to do with the #Transient annotation ?! I wonder whether I have a coding or design issue? I guess my question is: how to model this "give me only the last element from a list" in a JPA entity class (without too much boilerplate code)?
Thank you for your help!
For your convenience please find following some related code snippets:
#Entity
#Inheritance
#Access(AccessType.PROPERTY) // JPA reading and writing attributes through their accessor getter and setter methods
public abstract class UserRequirement extends Requirement implements Serializable {
..
protected List<CostEstimate> costEstimates; // Money needed
..
protected UserRequirement() {
..
costEstimates = FXCollections.observableArrayList();
setLastCostEstimate(new CostEstimate(0));
..
}
..
#OneToMany(mappedBy="parent", orphanRemoval = true, cascade = CascadeType.PERSIST, fetch = FetchType.LAZY)
public List<CostEstimate> getCostEstimates() {
return costEstimates;
}
#SuppressWarnings("unused") // Used by JPA
public void setCostEstimates(List<CostEstimate> newCostEstimates) {
if(newCostEstimates != null) {
((ObservableList<CostEstimate>)costEstimates).setAll(newCostEstimates);
} else {
costEstimates.clear();
}
}
#Transient
public CostEstimate getLastCostEstimate() {
return costEstimates.get(costEstimates.size()-1);
}
public void setLastCostEstimate(CostEstimate costEstimate) {
if(costEstimate = null) {
return;
}
costEstimates.add(costEstimate);
}
..
}
i need to do something like this
String myVar = "myString";
...
#Preauthorize("customMethod(myVar)")
public void myMethod() {
...
}
but I'm failing at it. How can I do that? It says it cannot be resolved
EDIT:I'm decoupling few rest services and sometimes I have to share infos between them
#Value("${my-properties}")
String urlIWantToShare;
...
#PreAuthorize("isValid(#myValue,urlIWantToShare)")
#RequestMapping(value = "**/letsCheckSecurityConfig", method = RequestMethod.GET)
public boolean letsCheckSecurityConfig(#RequestHeader(name = "MY-VALUE") String myValue)) {
return true;
}
this "isValid" custom security method will call an external service, that doesn't know anything about the caller and his infos. I need to transmit few infos and I need to take them from different kind of sources
One of the sources is my application.properties
EDIT2: I managed to do this
#PreAuthorize("isValid(#myValue, #myProperty)")
#RequestMapping(value = "**/letsCheckSecurityConfig", method = RequestMethod.GET)
public boolean letsCheckSecurityConfig(#RequestHeader(name = "MY-VALUE") String myValue,
#Value("${my-property-from-app-properties}") String myProperty))
..but I want to use not only actual static properties but runtime one. Any help?
You can create a wrapper method without parameters which will call the desired method with parameters. In the annotation you can use the method without parameters
Apologies if I have misunderstood what you are trying to do, but from my understanding you're trying to set an annotation at runtime based on a variable / app.properties, so that you can then read this variable and then execute your class?
If this is the case, You cannot do this from an annotation alone as annotations cannot read local variables and cannot be set at runtime.
However, one option for you is to have an object which contains the 'values' of interest for you and then read the values from the object.
Something like the below:
PoJo
public class testObject{
#test
private String myVar;
private String myValue;
//Getters and Setters
}
Get Object values
public void getFields (Object obj){
Field fields = obj.getClass().getDeclaredFields();
for (Field f : fields){
test fieldAnnotation = f.getAnnotation(test.Class);
if (fieldAnnotation != null){
f.get(obj);
// Do checks based on this
}
}
}
Main Class
public static void main(String[] args){
//Create object
testObject test = new testObject();
test.setOne("testOne");
test.setTwo("testTwo");
getFields(test);
}
I've pulled this code based on what I had to do to get the fields - but in my case, I did not know the object types I was going to be passed. You are simply using the annotation to 'mark' the fields you want to retrieve and then reading the value from the object.
If you're in a similar situation, then you can see my answer here: initial answer
Let me know if i've misunderstood this and I can try and further clarify my answer.
I am trying to submit a form from Ext JS 4 to a Spring 3 Controller using JSON. I am using Jackson 1.9.8 for the serialization/deserialization using Spring's built-in Jackson JSON support.
I have a status field that is initially null in the Domain object for a new record. When the form is submitted it generates the following json (scaled down to a few fields)
{"id":0,"name":"someName","status":""}
After submitted the following is seen in the server log
"nested exception is org.codehaus.jackson.map.JsonMappingException: Can not construct instance of com.blah.domain.StatusEnum from String value '': value not one of the declared Enum instance names"
So it appears that Jackson is expecting a valid Enum value or no value at all including an empty string. How do I fix this whether it is in Ext JS, Jackson or Spring?
I tried to create my own ObjectMapper such as
public class MyObjectMapper extends Object Mapper {
public MyObjectMapper() {
configure(DeserializationConfig.Feature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT, true);
}
}
and send this as a property to MappingJacksonMappingView but this didn't work. I also tried sending it in to MappingJacksonHttpMessageConverter but that didn't work. Side question: Which one should I be sending in my own ObjectMapper?
Suggestions?
The other thing you could do is create a specialized deserializer (extends org.codehaus.jackson.map.JsonDeserializer) for your particular enum, that has default values for things that don't match. What I've done is to create an abstract deserializer for enums that takes the class it deserializes, and it speeds this process along when I run into the issue.
public abstract class EnumDeserializer<T extends Enum<T>> extends JsonDeserializer<T> {
private Class<T> enumClass;
public EnumDeserializer(final Class<T> iEnumClass) {
super();
enumClass = iEnumClass;
}
#Override
public T deserialize(final JsonParser jp,
final DeserializationContext ctxt) throws IOException, JsonProcessingException {
final String value = jp.getText();
for (final T enumValue : enumClass.getEnumConstants()) {
if (enumValue.name().equals(value)) {
return enumValue;
}
}
return null;
}
}
That's the generic class, basically just takes an enum class, iterates over the values of the enum and checks the next token to match any name. If they do it returns it otherwise return null;
Then If you have an enum MyEnum you'd make a subclass of EnumDeserializer like this:
public class MyEnumDeserializer extends EnumDeserializer<MyEnum> {
public MyEnumDeserializer() {
super(MyEnum.class);
}
}
Then wherever you declare MyEnum:
#JsonDeserialize(using = MyEnumDeserializer.class)
public enum MyEnum {
...
}
I'm not familiar with Spring, but just in case, it may be easier to handle that on the client side:
Ext.define('My.form.Field', {
extend: 'Ext.form.field.Text',
getSubmitValue: function() {
var me = this,
value;
value = me.getRawValue();
if ( value === '' ) {
return ...;
}
}
});
You can also disallow submitting empty fields by setting their allowBlank property to false.
Ended up adding defaults in the EXT JS Model so there is always a value. Was hoping that I didn't have to this but it's not that big of a deal.
I have the same issue. I am reading a JSON stream with some empty strings. I am not in control of the JSON stream, because it is from a foreign service. And I am always getting the same error message. I tried this here:
mapper.getDeserializationConfig().with(DeserializationConfig.Feature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT);
But without any effect. Looks like a Bug.