JarCastingGetting Started
pom.xml
<dependency>
<groupId>com.github.lazaronixon</groupId>
<artifactId>active-persistence</artifactId>
<version>0.0.31</version>
</dependency>
models/User.java
@Entity
public class User extends BaseIdentity {
private String name;
private String occupation;
private LocalDateTime createdAt;
private LocalDateTime updatedAt;
// Get/Set omitted by brevity
}
repositories/UserRepository.java
@RequestScoped
public class UserRepository extends Base<User> {
}
CRUD: Reading and Writing Data
Create
User user = new User();
user.name = "David";
user.occupation = "Code Artist";
userRepository.save(user);
Read
// return a collection with all users
List<User> users = userRepository.all();
// return the first user
User user = userRepository.first();
// return the first user named David
User david = userRepository.findBy("user.name = ?", "David");
// find all users named David who are Code Artists and sort by createdAt in reverse chronological order
List<User> users = userRepository.where("user.name = 'David' AND user.occupation = 'Code Artist'").order("user.createdAt DESC");
Update
User user = userRepository.findBy("user.name = ?", "David");
user.name = "Dave";
userRepository.save(user);
//OR
userRepository.updateAll("user.maxLoginAttempts = 3, user.mustChangePassword = 'true'");
Delete
User user = userRepository.findBy("user.name = ?", "David");
userRepository.destroy(user);
//OR
userRepository.destroyBy("user.name = ?", "David");
userRepository.destroyAll();
Callbacks
public class ClientRepository extends Base<Client> {
@Override
public void beforeSave(Client client) {
// implementation here
}
@Override
public void afterSave(Client client) {
// implementation here
}
@Override
public void beforeCreate(Client client) {
// implementation here
}
@Override
public void afterCreate(Client client) {
// implementation here
}
@Override
public void beforeUpdate(Client client) {
// implementation here
}
@Override
public void afterUpdate(Client client) {
// implementation here
}
@Override
public void beforeDestroy(Client client) {
// implementation here
}
@Override
public void afterDestroy(Client client) {
// implementation here
}
}
TimeStamps
public class Post extends BaseIdentity {
private LocalDateTime createdAt;
private LocalDateTime updatedAt;
@Override
public void setCreatedAt(LocalDateTime createdAt) {
this.createdAt = createdAt;
}
@Override
public void setUpdatedAt(LocalDateTime updatedAt) {
this.updatedAt = updatedAt;
}
}
Retrieving Objects from the Database
Retrieving a Single Object
// Find the client with primary key (id) 10.
Client client = clientRepository.find(10);
// The take method retrieves a record without any implicit ordering
Client client = clientRepository.take();
List<Client> clients = clientRepository.take(2);
// The first method finds the first record ordered by primary key (default)
Client client = clientRepository.first();
Client client = clientRepository.order("client.firstName").first();
List<Client> clients = clientRepository.first(3);
// The last method finds the last record ordered by primary key (default)
Client client = clientRepository.last();
Client client = clientRepository.order("client.firstName").last();
List<Client> clients = clientRepository.last(3);
// The findBy method finds the first record matching some conditions
Client client = clientRepository.findBy("client.firstName = ?", "Lifo"); // #<Client id: 1, firstName: "Lifo">
Client client = clientRepository.findBy("client.firstName = ?", "Jon"); // null
Client client = clientRepository.findBy$("client.firstName = ?", "does not exist"); // EntityNotFoundException
Conditions
//Ordinal Conditions
clientRepository.where("client.ordersCount = ?", 10);
clientRepository.where("client.ordersCount = ? AND client.locked = ?", 10, false);
//Placeholder Conditions
clientRepository.where("client.ordersCount = :count", Map.of("count", 10));
clientRepository.where("client.ordersCount = :count AND client.locked = :locked", Map.of("count", 10, "locked", false));
//SubQuery Conditions
var subquery = clientRepository.select("order.client.id");
clientRepository.where("client.id IN (?), subquery);
Ordering
clientRepository.order("client.createdAt");
clientRepository.order("client.createdAt DESC");
clientRepository.order("client.createdAt ASC");
Selecting Specific Fields
List<Client> client = clientRepository.select("client.viewableBy", "client.locked");
List<Client> client = clientRepository.select("client.name").distinct();
Limit and Offset
clientRepository.limit(5);
clientRepository.limit(5).offset(30);
Group
List<Order> orders = orderRepository.select("date(order.createdAt)", "sum(order.price)").group("date(order.createdAt)");
Total of grouped items
Map<String, Long> result = (Map) orderRepository.group("order.status").count(); // => { 'awaiting_approval' => 7, 'paid' => 12 }
Having
List<Order> orders = orderRepository.select("date(order.createdAt)", "sum(order.price)").group("date(order.createdAt)").having("sum(order.price) > 100");
Overriding Conditions
Unscope
orderRepository.where("order.id > 10").limit(20).order("order.id asc").unscope(ORDER);
Only
orderRepository.where("order.id > 10").limit(20).order("order.id asc").only(ORDER);
Reselect
postRepository.select("post.title", "post.body").reselect("post.createdAt");
Reorder
postRepository.order("post.title").reorder("post.createdAt");
Rewhere
articleRepository.where("article.trashed = true").rewhere("article.trashed = false");
Null Relation
studentRepository.none(); // returns an empty Relation and fires where 1=0.
Locking Records for Update
Client client = clientRepository.lock().first();
// OR
Client client = clientRepository.lock(true).first();
// OR
Client client = clientRepository.lock(PESSIMISTIC_WRITE).first();
Readonly Objects
Client client = clientRepository.readonly().first();
client.visits = 1;
clientRepository.save(); // ReadOnlyRecord Exception
Joining Tables
authorRepository.joins("JOIN author.post post");
Eager Loading Associations (EclipseLink only)
clientRepository.includes("client.address").limit(10);
clientRepository.eagerLoads("client.address").limit(10);
Scopes
Applying a default scope
public class ClientRepository extends Base<Client> {
@Override
public Relation<Client> defaultScope() {
return where("client.name = 'nixon'");
}
}
clientRepository.all(); // SELECT client FROM Client client WHERE client.name = 'nixon'
clientRepository.unscoped().all(); // SELECT client FROM Client client
Merging of scopes
userRepository.merge(active());
Removing All Scoping
clientRepository.unscoped();
clientRepository.where("client.published = false").unscoped();
Dynamic Finders
Client client = clientRepository.findByExpression("Name", "Nixon");
Client client = clientRepository.findByExpression("NameAndLocked", "Nixon", true);
// OR
Client client = clientRepository.findByExpression$("Name", "not found"); // EntityNotFoundException
Finding by SQL/JPQL
List<Post> posts = postRepository.findBySql("SELECT id, title FROM Post WHERE id = 5").getResultList();
List<Post> posts = postRepository.findByJpql("SELECT p FROM Post p WHERE p.id = 5").getResultList();
// OR
List posts = postRepository.getConnection().selectAll("SELECT id, title FROM Post WHERE id = 5", QueryType.SQL).getResultList();
List posts = postRepository.getConnection().selectAll("SELECT p FROM Post p WHERE p.id = 5", QueryType.JPQL).getResultList();
Existence of Objects
boolean exists = studentRepository.exists("student.name = 'Lifo'");
boolean exists = studentRepository.where("student.name = 'Lifo'").exists();
Pluck
List<Integer> ids = clientRepository.where("client.active = true").pluck("client.id"); //[1, 2, 3]
List<Integer> ids = clientRepository.where("client.active = true").ids; //[1, 2, 3]
Calculations
long count = (long) clientRepository.count();
long count = (long) clientRepository.count("client.age");
int minimum = (int) clientRepository.minimum("client.age");
int maximum = (int) clientRepository.maximum("client.age");
long total = (long) clientRepository.sum("client.ordersCount");
double average = (double) clientRepository.average("client.ordersCount");
Recommended Environment
- Java 9
- JakartaEE 8
- Payara Server
Testing
- Install Payara Server >= 5.201
- Add Resources - ./asadmin add-resources path_to/payara-resources.xml