Holon platform Core module
Latest release: 5.5.0
This is the core module of the Holon Platform and represents the platform foundation, providing the definition of the overall architecture, base structures and APIs.
The module highlights are:
Context
resources- Configuration APIs
- Data validation APIs
- Localization and internationalization support
- The
Property
model and theDatastore
API - Java Beans support
- RESTful Java client
- Authentication and authorization
- JSON Web Tokens (
JWT
) support - Spring, Spring Security and Spring Boot integration
- Spring tenant scope
See the module documentation for details.
Just like any other platform module, this artifact is part of the Holon Platform ecosystem, but can be also used as a stand-alone library.
See Getting started and the platform documentation for further details.
At-a-glance overview
Property model definition:
public interface Subject {
static NumericProperty<Long> ID = NumericProperty.longType("id");
static StringProperty NAME = StringProperty.create("name");
static StringProperty SURNAME = StringProperty.create("surname");
static TemporalProperty<LocalDate> BIRTH = TemporalProperty.localDate("birth");
static BooleanProperty ACTIVE = BooleanProperty.create("active");
static VirtualProperty<String> FULL_NAME = VirtualProperty.create(String.class,
propertyBox -> propertyBox.getValue(NAME) + " " + propertyBox.getValue(SURNAME));
static PropertySet<?> SUBJECT = PropertySet.of(ID, NAME, SURNAME, BIRTH, ACTIVE, FULL_NAME);
}
Property configuration:
static StringProperty NAME = StringProperty.create("name").message("Name").messageCode("localization.name")
.withConfiguration("my-config", "my-value");
Property value converter:
static StringProperty INTEGER_MODEL = StringProperty.create("integer_value").converter(Integer.class,
integer -> String.valueOf(integer), string -> Integer.valueOf(string));
Property validators:
static StringProperty NAME = StringProperty.create("name")
.withValidator(Validator.notBlank()).withValidator(Validator.max(50));
Property presenters and renderers:
String value = NAME.present("A value");
MyType myType = NAME.render(MyType.class);
PropertyBox:
PropertyBox propertyBox = PropertyBox.create(SUBJECT);
String name = propertyBox.getValue(NAME);
Optional<String> oname = propertyBox.getValueIfPresent(NAME);
propertyBox.setValue(NAME, "John");
propertyBox.propertyValues().forEach(propertyValue -> {
Property<?> property = propertyValue.getProperty();
Object value = propertyValue.getValue();
});
Datastore:
DataTarget<?> TARGET = DataTarget.named("subjects");
Datastore datastore = getDatastore();
Stream<PropertyBox> results = datastore.query().target(TARGET)
.filter(NAME.contains("a").and(SURNAME.isNotNull())).sort(BIRTH.desc()).stream(SUBJECT);
Stream<String> names = datastore.query(TARGET).aggregate(SURNAME).stream(NAME.max());
Optional<String> name = datastore.query(TARGET).filter(ID.eq(1L)).findOne(NAME);
datastore.insert(TARGET, PropertyBox.builder(SUBJECT).set(ID, 1L).set(NAME, "John").set(ACTIVE, true).build());
datastore.bulkUpdate(TARGET).set(ACTIVE, true).filter(BIRTH.lt(LocalDate.now())).execute();
datastore.query(TARGET).filter(ID.eq(1L)).findOne(SUBJECT).ifPresent(subject -> datastore.delete(TARGET, subject));
Bean PropertySet and Datastore:
class MyBean {
private @NotNull Long id;
private @Caption("The name") String name;
private @Caption("The surname") String surname;
/* getters and setters omitted */
}
BeanPropertySet<MyBean> propertySet = BeanPropertySet.create(MyBean.class);
PathProperty<?> name = propertySet.property("name");
PathProperty<String> typedName = propertySet.property("name", String.class);
BeanDatastore datastore = BeanDatastore.of(getDatastore());
Stream<MyBean> results = datastore.query(MyBean.class).filter(propertySet.property("name").eq("John")).stream();
datastore.save(new MyBean());
Realm:
Realm realm = Realm.builder().withAuthenticator(Authenticator.create(MyAuthenticationToken.class, token -> {
if ("test".equals(token.getPrincipal())) {
return Authentication.builder("test").withPermission("ROLE1").build();
}
throw new UnknownAccountException();
}))
.withDefaultAuthorizer().build();
Realm.builder().withAuthenticator(Account.authenticator(id -> Optional.of(Account.builder(id).build()))).build();
AuthContext:
AuthContext context = AuthContext.create(realm);
context.authenticate(AuthenticationToken.accountCredentials("test", "pwd"));
Optional<Authentication> authentication = context.getAuthentication();
boolean permitted = context.isPermitted("ROLE1", "ROLE2");
RestClient:
RestClient client = RestClient.forTarget("https://rest.api.example");
ResponseEntity<TestData> response = client.request()
.path("test/{id}").resolve("id", 123)
.accept(MediaType.APPLICATION_JSON)
.header("MY_HEADER", "my-value")
.authorizationBearer("An389fz56xsr7")
.get(TestData.class);
HttpStatus status = response.getStatus();
Optional<TestData> payload = response.getPayload();
Optional<TestData> data = client.request().path("test/{id}").resolve("id", 123)
.getForEntity(TestData.class);
List<TestData> results = client.request().path("test").getAsList(TestData.class);
client.request().path("test").post(RequestEntity.json(new TestData()));
Optional<PropertyBox> propertyBox = client.request().path("test2")
.propertySet(PROPERTIES).getForEntity(PropertyBox.class);
LocalizationContext:
LocalizationContext localizationContext = LocalizationContext.builder()
.withMessageProvider(MessageProvider.fromProperties("messages").build())
.withDefaultDateTemporalFormat(TemporalFormat.MEDIUM)
.withInitialLocale(Locale.US)
.build();
localizationContext.localize(Locale.ITALY);
String localized = localizationContext.getMessage("message.code", "Default message");
String formatted = localizationContext.format(LocalDate.now());
formatted = localizationContext.format(123.4d);
Optional<LocalizationContext> current = LocalizationContext.getCurrent();
See the module documentation for the user guide and a full set of examples.
Code structure
See Holon Platform code structure and conventions to learn about the "real Java API" philosophy with which the project codebase is developed and organized.
Getting started
System requirements
The Holon Platform is built using Java 8, so you need a JRE/JDK version 8 or above to use the platform artifacts.
Releases
See releases for the available releases. Each release tag provides a link to the closed issues.
Obtain the artifacts
The Holon Platform is open source and licensed under the Apache 2.0 license. All the artifacts (including binaries, sources and javadocs) are available from the Maven Central repository.
The Maven group id for this module is com.holon-platform.core
and a BOM (Bill of Materials) is provided to obtain the module artifacts:
Maven BOM:
<dependencyManagement>
<dependency>
<groupId>com.holon-platform.core</groupId>
<artifactId>holon-bom</artifactId>
<version>5.5.0</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencyManagement>
See the Artifacts list for a list of the available artifacts of this module.
Using the Platform BOM
The Holon Platform provides an overall Maven BOM (Bill of Materials) to easily obtain all the available platform artifacts:
Platform Maven BOM:
<dependencyManagement>
<dependency>
<groupId>com.holon-platform</groupId>
<artifactId>bom</artifactId>
<version>${platform-version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencyManagement>
See the Artifacts list for a list of the available artifacts of this module.
Build from sources
You can build the sources using Maven (version 3.3.x or above is recommended) like this:
mvn clean install
Getting help
-
Check the platform documentation or the specific module documentation.
-
Ask a question on Stack Overflow. We monitor the
holon-platform
tag. -
Report an issue.
-
A commercial support is available too.
Examples
See the Holon Platform examples repository for a set of example projects.
Contribute
See Contributing to the Holon Platform.
Join the contribute Gitter room for any question and to contact us.
License
All the Holon Platform modules are Open Source software released under the Apache 2.0 license.
Artifacts list
Maven group id: com.holon-platform.core
Artifact id | Description |
---|---|
holon-core |
Platform core components, services and APIs |
holon-http |
HTTP messages support |
holon-async-http |
Asynchronous HTTP messages support |
holon-async-datastore |
Asynchronous Datastore API |
holon-auth |
Authentication and Authorization |
holon-auth-jwt |
JSON Web Tokens support |
holon-spring |
Spring integration |
holon-spring-security |
Spring Security integration |
holon-spring-boot |
Spring Boot integration |
holon-starter |
Base Spring Boot starter |
holon-starter-security |
Base Spring Boot starter with Spring Security integration |
holon-starter-test |
Base Spring Boot starter for Unit tests |
holon-bom |
Bill Of Materials |
holon-bom-platform |
Bill Of Materials including external dependencies |
documentation-core |
Documentation |