Руководство по Hibernate. Руководство по Hibernate
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Пример простого приложения.В предыдущих статьях из цикла, посвященного Hibernate мы рассмотрели базовые понятия и ключевые функции этого ORM фреймворка. В этой статье мы создадим небольшое приложение, которое резюмирует всё, о чём мы говорили до этого. Исходный код проекта можно скачать по ЭТОЙ ССЫЛКЕ. Итак, во-первых мы создадим POJO – класс Developer.java, который соотвтетсвует правилам POJO. Developer.java package net.proselyte.hibernate.example; public class Developer { private int id; private String firstName; private String lastName; private String specialty; private int experience; /** * Default Constructor */ public Developer() { } /** * Plain constructor */ public Developer(int id, String firstName, String lastName, String specialty, int experience) { this.id = id; this.firstName = firstName; this.lastName = lastName; this.specialty = specialty; this.experience = experience; } /** * Getters and Setters */ public int getId() { return id; } public void setId(int id) { this.id = id; } public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this.firstName = firstName; } public String getLastName() { return lastName; } public void setLastName(String lastName) { this.lastName = lastName; } public String getSpecialty() { return specialty; } public void setSpecialty(String specialty) { this.specialty = specialty; } public int getExperience() { return experience; } public void setExperience(int experience) { this.experience = experience; } /** * toString method (optional) */ @Override public String toString() { return "Developer{" + "id=" + id + ", firstName='" + firstName + '\'' + ", lastName='" + lastName + '\'' + ", specialty='" + specialty + '\'' + ", experience=" + experience + '}'; } } Вторым шагом будет создание таблицы в базе данных (далее – БД). HIBERNATE_DEVELOPERS CREATE TABLE HIBERNATE_DEVELOPERS( ID INT NOT NULL AUTO_INCREMENT, FIRST_NAME VARCHAR(50) DEFAULT NULL, LAST_NAME VARCHAR(50) DEFAULT NULL, SPECIALTY VARCHAR(50) DEFAULT NULL, EXPERIENCE INT DEFAULT NULL, PRIMARY KEY(ID) ); Шаг 3 – создание конфигурационного файла hibernate.cfg.xml hibernate.cfg.xml "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> org.hibernate.dialect.MySQLDialect com.mysql.jdbc.Driver ИМЯ ВАШЕЙ БД is the database name --> jdbc:mysql://localhost/ИМЯ_ВАШЕЙ_БАЗЫ_ДАННЫХ ВАШЕ ИМЯ ПОЛЬЗОВАТЕЛЯ ВАШ ПАРОЛЬ Четвёртый шаг – создание конфигурационного XML – файла Developer.hbm.xml Developer.hbm.xml "-//Hibernate/Hibernate Mapping DTD//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> This class contains developer's details. И финальный шаг – создание основного класса приложения DeveloperRunner.java DeveloperRunner.java package net.proselyte.hibernate.example; import net.proselyte.hibernate.example.model.Developer; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.Transaction; import org.hibernate.cfg.Configuration; import java.util.List; public class DeveloperRunner { private static SessionFactory sessionFactory; public static void main(String[] args) { sessionFactory = new Configuration().configure().buildSessionFactory(); DeveloperRunner developerRunner = new DeveloperRunner(); System.out.println("Adding developer's records to the DB"); /** * Adding developer's records to the database (DB) */ developerRunner.addDeveloper("Proselyte", "Developer", "Java Developer", 2); developerRunner.addDeveloper("Some", "Developer", "C++ Developer", 2); developerRunner.addDeveloper("Peter", "UI", "UI Developer", 4); System.out.println("List of developers"); /** * List developers */ List developers = developerRunner.listDevelopers(); for (Developer developer : developers) { System.out.println(developer); } System.out.println("==================================="); System.out.println("Removing Some Developer and updating Proselyte"); /** * Update and Remove developers */ developerRunner.updateDeveloper(10, 3); developerRunner.removeDeveloper(11); System.out.println("Final list of developers"); /** * List developers */ developers = developerRunner.listDevelopers(); for (Developer developer : developers) { System.out.println(developer); } System.out.println("==================================="); } public void addDeveloper(String firstName, String lastName, String specialty, int experience) { Session session = sessionFactory.openSession(); Transaction transaction = null; transaction = session.beginTransaction(); Developer developer = new Developer(firstName, lastName, specialty, experience); session.save(developer); transaction.commit(); session.close(); } public List listDevelopers() { Session session = this.sessionFactory.openSession(); Transaction transaction = null; transaction = session.beginTransaction(); List developers = session.createQuery("FROM Developer").list(); transaction.commit(); session.close(); return developers; } public void updateDeveloper(int developerId, int experience) { Session session = this.sessionFactory.openSession(); Transaction transaction = null; transaction = session.beginTransaction(); Developer developer = (Developer) session.get(Developer.class, developerId); developer.setExperience(experience); session.update(developer); transaction.commit(); session.close(); } public void removeDeveloper(int developerId) { Session session = this.sessionFactory.openSession(); Transaction transaction = null; transaction = session.beginTransaction(); Developer developer = (Developer) session.get(Developer.class, developerId); session.delete(developer); transaction.commit(); session.close(); } } Если все настройки были сделаны правильно, то мы получаем следующий результат работы программы: /usr/lib/jvm/java-8-oracle/bin/java -Didea.launcher.port=7538 -Didea.launcher.bin.path=/home/proselyte/Programming/Soft/IntellijIdea/bin -Dfile.encoding=UTF-8 -classpath /usr/lib/jvm/java-8-oracle/jre/lib/management-agent.jar:/usr/lib/jvm/java-8-oracle/jre/lib/plugin.jar:/usr/lib/jvm/java-8-oracle/jre/lib/rt.jar:/usr/lib/jvm/java-8-oracle/jre/lib/jsse.jar:/usr/lib/jvm/java-8-oracle/jre/lib/charsets.jar:/usr/lib/jvm/java-8-oracle/jre/lib/jce.jar:/usr/lib/jvm/java-8-oracle/jre/lib/resources.jar:/usr/lib/jvm/java-8-oracle/jre/lib/deploy.jar:/usr/lib/jvm/java-8-oracle/jre/lib/jfxswt.jar:/usr/lib/jvm/java-8-oracle/jre/lib/javaws.jar:/usr/lib/jvm/java-8-oracle/jre/lib/jfr.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/dnsns.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/sunpkcs11.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/sunec.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/sunjce_provider.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/jaccess.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/nashorn.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/localedata.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/zipfs.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/cldrdata.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/jfxrt.jar:/home/proselyte/Programming/IdeaProjects/ProselyteTutorials/Hibernate/target/classes:/home/proselyte/.m2/repository/org/springframework/spring-core/4.1.1.RELEASE/spring-core-4.1.1.RELEASE.jar:/home/proselyte/.m2/repository/commons-logging/commons-logging/1.1.3/commons-logging-1.1.3.jar:/home/proselyte/.m2/repository/org/springframework/spring-web/4.1.1.RELEASE/spring-web-4.1.1.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/spring-aop/4.1.1.RELEASE/spring-aop-4.1.1.RELEASE.jar:/home/proselyte/.m2/repository/aopalliance/aopalliance/1.0/aopalliance-1.0.jar:/home/proselyte/.m2/repository/org/springframework/spring-beans/4.1.1.RELEASE/spring-beans-4.1.1.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/spring-context/4.1.1.RELEASE/spring-context-4.1.1.RELEASE.jar:/home/proselyte/.m2/repository/javax/servlet/servlet-api/2.5/servlet-api-2.5.jar:/home/proselyte/.m2/repository/org/springframework/spring-webmvc/4.1.1.RELEASE/spring-webmvc-4.1.1.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/spring-expression/4.1.1.RELEASE/spring-expression-4.1.1.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/integration/spring-integration-file/4.2.1.RELEASE/spring-integration-file-4.2.1.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/integration/spring-integration-core/4.2.1.RELEASE/spring-integration-core-4.2.1.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/spring-messaging/4.2.2.RELEASE/spring-messaging-4.2.2.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/retry/spring-retry/1.1.2.RELEASE/spring-retry-1.1.2.RELEASE.jar:/home/proselyte/.m2/repository/org/springframework/spring-tx/4.2.2.RELEASE/spring-tx-4.2.2.RELEASE.jar:/home/proselyte/.m2/repository/commons-io/commons-io/2.4/commons-io-2.4.jar:/home/proselyte/.m2/repository/org/hibernate/hibernate-core/5.0.7.Final/hibernate-core-5.0.7.Final.jar:/home/proselyte/.m2/repository/org/jboss/logging/jboss-logging/3.3.0.Final/jboss-logging-3.3.0.Final.jar:/home/proselyte/.m2/repository/org/hibernate/javax/persistence/hibernate-jpa-2.1-api/1.0.0.Final/hibernate-jpa-2.1-api-1.0.0.Final.jar:/home/proselyte/.m2/repository/org/javassist/javassist/3.18.1-GA/javassist-3.18.1-GA.jar:/home/proselyte/.m2/repository/antlr/antlr/2.7.7/antlr-2.7.7.jar:/home/proselyte/.m2/repository/org/apache/geronimo/specs/geronimo-jta_1.1_spec/1.1.1/geronimo-jta_1.1_spec-1.1.1.jar:/home/proselyte/.m2/repository/org/jboss/jandex/2.0.0.Final/jandex-2.0.0.Final.jar:/home/proselyte/.m2/repository/dom4j/dom4j/1.6.1/dom4j-1.6.1.jar:/home/proselyte/.m2/repository/xml-apis/xml-apis/1.0.b2/xml-apis-1.0.b2.jar:/home/proselyte/.m2/repository/org/hibernate/common/hibernate-commons-annotations/5.0.1.Final/hibernate-commons-annotations-5.0.1.Final.jar:/home/proselyte/.m2/repository/mysql/mysql-connector-java/5.1.38/mysql-connector-java-5.1.38.jar:/home/proselyte/Programming/Soft/IntellijIdea/lib/idea_rt.jar com.intellij.rt.execution.application.AppMain net.proselyte.hibernate.example.DeveloperRunner Feb 18, 2016 2:30:00 PM org.hibernate.Version logVersion INFO: HHH000412: Hibernate Core {5.0.7.Final} Feb 18, 2016 2:30:00 PM org.hibernate.cfg.Environment INFO: HHH000206: hibernate.properties not found Feb 18, 2016 2:30:00 PM org.hibernate.cfg.Environment buildBytecodeProvider INFO: HHH000021: Bytecode provider name : javassist Feb 18, 2016 2:30:00 PM org.hibernate.annotations.common.reflection.java.JavaReflectionManager INFO: HCANN000001: Hibernate Commons Annotations {5.0.1.Final} Feb 18, 2016 2:30:02 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure WARN: HHH10001002: Using Hibernate built-in connection pool (not for production use!) Feb 18, 2016 2:30:02 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator INFO: HHH10001005: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://localhost/PROSELYTE_TUTORIAL] Feb 18, 2016 2:30:02 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator INFO: HHH10001001: Connection properties: {user=root, password=****} Feb 18, 2016 2:30:02 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator INFO: HHH10001003: Autocommit mode: false Feb 18, 2016 2:30:02 PM org.hibernate.engine.jdbc.connections.internal.PooledConnections INFO: HHH000115: Hibernate connection pool size: 20 (min=1) Thu Feb 18 14:30:02 EET 2016 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification. Feb 18, 2016 2:30:02 PM org.hibernate.dialect.Dialect INFO: HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect Adding developer's records to the DB List of developers Feb 18, 2016 2:30:03 PM org.hibernate.hql.internal.QueryTranslatorFactoryInitiator initiateService INFO: HHH000397: Using ASTQueryTranslatorFactory Developer: id: 10 First Name: Proselyte Last Name: Developer Specialty: Java Developer Experience: 2 Developer: id: 11 First Name: Some Last Name: Developer Specialty: C++ Developer Experience: 2 Developer: id: 12 First Name: Peter Last Name: UI Specialty: UI Developer Experience: 4 =================================== Removing Some Developer and updating Proselyte Final list of developers Developer: id: 10 First Name: Proselyte Last Name: Developer Specialty: Java Developer Experience: 3 Developer: id: 12 First Name: Peter Last Name: UI Specialty: UI Developer Experience: 4 =================================== В этой статье мы создали простейшее приложение с использование Hibernate. Прим. если у Вас возникают проблемы с редактированием и удалением пользователей – обратите внимание на ID разработчиков. Виды связей. До этого момента мы рассматривали только простейшие виды связей между классами и таблицами в базах данных (далее – БД). Но давайте рассмотрим более детально виды связей в ORM. Связи в ORM деляся на 3 гурппы: Связывание коллекций Ассоциативное связывание Связывание компоннетов Рассмотрим каждую из них: Связывание коллекций Если среди значений класса есть коллекции (collections) каких-либо значений, мы можем связать (map) их с помощью любого интерфейса коллекций, доступных в Java. В Hibernate мы можем оперировать следующими коллекциями: java.util.List (ссылка на пример) Связывается (mapped) с помощью элемента
java.util.Collection (ссылка на пример) Связывается (mapped) с помощью элементов java.util. Set (ссылка на пример) Связывается (mapped) с помощью элемента java.util.SortedSet (ссылка на пример) Связывается (mapped) с помощью элемента java.util.Map (ссылка на пример) Связывается (mapped) с помощью элемента |