what is the best way to represent the below properties in Spring for each category? Currently we have implemented for aaa properties. We always have two fields for each category.
We want to use the same POJO for all categories. Please suggest the best approach that fits.
Property file name package.properties
category.aaa.field1 = value1
category.aaa.field2 = value2
category.bbb.field1 = value1
category.bbb.field2 = value2
category.ccc.field1 = value1
category.ccc.field2 = value2
category.ddd.field1 = value1
category.ddd.field2 = value2
We have created a POJO with
#Data
public class CategoryPojo{
private String valueOne;
private String valueTwo;
}
we are reading it in #Configuration using #PropertySource
#Configuration
#ComponentScan(value = "com.category")
#PropertySource("classpath:package.properties")
public class CategoryConfig{
#Value("${category.aaa.field1}")
private String fieldOne;
#Value("${category.aaa.field2}")
private String fieldTwo;
#Bean(name = "getACategory")
public CategoryPojo getFields() {
return new CategoryPojo(fieldOne, fieldTwo);
}
}
You can, and should, use https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-external-config.html#boot-features-external-config-typesafe-configuration-properties
To handle this.
#Data
#ConfigurationProperties(prefix="category")
public class MyProperties{
private CategoryPojo aaa;
private CategoryPojo bbb;
private CategoryPojo ccc;
private CategoryPojo ddd;
#Data
public static class CategoryPojo{
private String valueOne;
private String valueTwo;
}
}
You can then place #EnableConfigurationProperties(classes = MyProperties.class) on your main application class or another #Configuration and then #Autowire your MyProperties class where its needed.
Related
I am trying to use MapStruct for a structure similar to the following:
#Data
public class ClassAEntity {
private int id;
private String name;
private String numT;
private List<ClassBEntity) bs;
}
#Data
public class ClassBEntity {
private int id;
private String name;
private String numT;
private List<Other> oc;
}
#Data
public class ClassA {
private int id;
private String name;
private List<ClassB) bs;
}
#Data
public class ClassB {
private int id;
private String name;
private List<Other> oc;
}
In the interface I have added the following mapping:
ClassAEntity map(ClassA classA, String numT)
I get a warning because it can't map numT to classBEntity.numT and I can't add it with #Mapping in the following way:
#Mapping(source = "numT", target = "bs[].numT")
On the other hand I need to ignore the parameter oc of classBEntity because "Other" object contains classAEntity and forms a cyclic object. (because I use oneToMany JPA). I have tried the following:
#Mapping(target = "bs[].oc", ignore = true)
Thank you for your help
MapStruct does not support defining nested mappings for collections. You will have to define more explicit methods.
For example to map numT into bs[].numT and ignore bs[].oc you'll need to do something like:
#Mapper
public MyMapper {
default ClassAEntity map(ClassA classA, String numT) {
return map(classA, numT, numT);
}
ClassAEntity map(ClassA classA, String numT, #Context String numT);
#AfterMapping
default void setNumTOnClassBEntity(#MappingTarget ClassBEntity classB, #Context String numT) {
classB.setNumT(numT);
}
#Mapping(target = "oc", ignore = "true")
ClassBEntity map(ClassB classB);
}
I'm trying to create compoundIndex on document in Spring. I could create manually on Mongoshell. But in Spring it's not working. Here is my code.
Document(collection = "Cars")
#CompoundIndexes({
#CompoundIndex(def = "{'brand':1,'model':1,'colour':1,'fuelTypes':1}", name = "cars_compound_indexes",unique = true)
})
public class Car {
private String brand;
private String model;
private List<FuelType> fuelTypes;
private String colour;
}
And also how can I update document when duplicate is entered.
I have the QueueContent class that it has is a superclass of two others.
I get a String in JSON format that contains the information I need to extract. The super class is:
#Data
#JsonIgnoreProperties(ignoreUnknown = true)
public class QueueContent {
private String empresa;
private String empresa_cor;
private String empresa_contato;
private String empresa_url;
private String empresa_telefone;
private String empresa_idioma;
public QueueContent(String empresa, String empresa_cor, String empresa_contato, String empresa_url, String empresa_telefone, String empresa_idioma) {
this.empresa = empresa;
this.empresa_cor = empresa_cor;
this.empresa_contato = empresa_contato;
this.empresa_url = empresa_url;
this.empresa_telefone = empresa_telefone;
this.empresa_idioma = empresa_idioma;
}
public QueueContent() {
}
}
I'm using Lombok to generate Getters / Setters)
This is the child class:
#Data
public class EmailCameraOffline extends QueueContent {
private Timestamp camera_last_online;
private String camera_nome;
private String empresa_url_plataforma;
public EmailCameraOffline(String empresa, String empresa_cor, String empresa_contato, String empresa_url, String empresa_telefone, String empresa_idioma, Timestamp camera_last_online, String camera_nome, String empresa_url_plataforma) {
super(empresa, empresa_cor, empresa_contato, empresa_url, empresa_telefone, empresa_idioma);
this.camera_last_online = camera_last_online;
this.camera_nome = camera_nome;
this.empresa_url_plataforma = empresa_url_plataforma;
}
public EmailCameraOffline() {
}
}
So I've done:
EmailCameraOffline infosEmail = new ObjectMapper().readValue(content, EmailCameraOffline.class);
System.out.println(infosEmail);
And the output is:
EmailCameraOffline (camera_last_online = 2020-03-12 03: 01: 45.0, camera_nome = Pier Cam 1, empresa_url_platform = null)
How do I get my EmailCameraOffline object to have the superclass attributes initialized?
Everything should be loaded and initialized just fine, so calling:
System.out.println(infosEmail.getEmpresa());
should give expected value.
Problem
The problem is in the default implementation of toString() method (done via #Data) at EmailCameraOffline class, which does not include inherited fields.
Solution
To fix this you can "override" #Data's toString() implementation to include inherited fields as well using Lombok as:
#Data
#ToString(callSuper = true)
public class EmailCameraOffline extends QueueContent {
...
}
#Component
public class Bot extends TelegramLongPollingBot {
#Value("${camel.component.telegram.authorization-token}") //properties
private String botToken; //null
TelegramBot bot = TelegramBotAdapter.buildDebug(botToken);
.
.
.
}
I don't understand why is not injected a param value defined in properties.
Notice that #Value do not support relaxed binding, so check your property.
#Component
#PropertySource("file:${app_env_path}/${app_env}_DBconnection.properties")
public class DBProperties {
#Value("${driver.class.name}")
private String driverClassName;
#Value("${db.url}")
private String url;
#Value("${db.username}")
private String username;
#Value("${db.password}")
private String password;
#Value("${db.poolsize}")
private String poolsize;
//setters and getters
}
Property file -
driver.class.name=oracle.jdbc.OracleDriver
db.url=
db.username=
db.password=
db.poolsize=100
app_env_path = path where the location of the file
app_env = SIT/PROD
Many times I'm faced with a class which constructor method must contain list of arguments that is identical with the list of class instance variables.
As you see in the example there is "SOME" code to make this hapend.
I'm wondering how can I make this process less painful?
Example:
public class VimeoUser extends Schema {
#Getter #Setter private String uri;
#Getter #Setter private String name;
#Getter #Setter private String link;
#Getter #Setter private String location;
#Getter #Setter private String bio;
#Getter #Setter private String createdTime;
#Getter #Setter private String account;
#Getter #Setter private Map<String,Integer> statistics = new HashMap<>();
#Getter #Setter private List<Website> websites = new ArrayList<>();
#Getter #Setter private List<Portrait> portraits = new ArrayList<>();
public VimeoUser(
String uri,
String name,
String link,
String location,
String bio,
String createdTime,
String account,
Map<String,Integer> statistics,
List<Website> websites,
List<Portrait> portraits){
this.uri = uri;
this.name = name;
this.link = link;
this.location = location;
this.bio = bio;
this.createdTime = createdTime;
this.account = account;
this.statistics = statistics;
this.websites = websites;
this.portraits = portraits;
}
}
It is possible to use a pattern named Builder. It is explained in this question
Basically it works as following:
Create an inner static class Builder
Create a private constructor that take as an argument an object of type Builder
In the Builder class add methods that set a single value and returns this (current reference to instance of the Builder class)
In the body of the constructor of your class use the values passed in the Builder to set each property
add a method build in the Builder that calls the private constructor of your class
Here is an example:
public class NutritionalFacts {
private int sodium;
private int fat;
private int carbo;
public class Builder {
private int sodium;
private int fat;
private int carbo;
public Builder(int s) {
this.sodium = s;
}
public Builder fat(int f) {
this.fat = f;
return this;
}
public Builder carbo(int c) {
this.carbo = c;
return this;
}
public NutritionalFacts build() {
return new NutritionalFacts(this);
}
}
private NutritionalFacts(Builder b) {
this.sodium = b.sodium;
this.fat = b.fat;
this.carbo = b.carbo;
}
}
and to use it do the following:
NutritionalFacts nutritionalFacts = new NutritionalFacts.Builder()
.fat(200).carbo(50).build();
Using this pattern instead of pojo with setter and getter is useful because it is possible to use it also to build immutable objects (objects with all final fields). An immutable object is useful if you need to share it on a multithreaded environment because it is not necessary to synchronize the access to it.
Additionally it is possible to add some controls in the build method to be sure that all fields are setted as expected.
I guess writing pojos for database modelling does not necessarily needs constructor other than default no-arg constructor. If anyway required in some situations, Getters and setters can be used.
Builder pattern
If you want create a object with more readable way, you can use a simple builder pattern. Lombok support this such as #Getter or #Setter. You just add #Builder annotation and everything should works fine.
#Getter
#Builder
public class SomeClass {
private final String valueOne;
private final String valueTwo;
}
And then you can create object in this way.
SomeClass someClass = SomeClass.builder()
.valueOne("one")
.valueTwo("two")
.build();
Fluent accessors method
Alternative way to create a class is using #Accessors annotation with fluent = true. Then you can create a empty object and set the value what you needed in simple way.
#Getter
#Setter
#Accessors(fluent = true)
public class SomeClass {
private String valueOne;
private String valueTwo;
}
Simple sample using this way.
SomeClass someClass = new SomeClass()
.valueOne("one")
.valueTwo("two");
I see you are already using Lombok. There is a #AllArgsConstructor class-level annotation that will generate the constructor for you. If you want the default constructor, too, use #NoArgsConstructor additionally.
More info on the constructor-generating annotations here.