需要配置多个数据源的Spring启动应用程序。多数据源配置使用单独的datasource、entityManager和transactionManager。
此外，hibernate命名配置使用以下配置的单个数据源。spring.jpa.hibernate.naming.physical-strategy=org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy
可以为entityManager提供上述配置的JPA属性。但无法在SpringPhysicalNamingStrategy中添加动态表名(来自application.properties(。
我创建了一个自定义的物理命名策略。它可以通过环境变量更改名称。此外，它还可以更改列名。名称标识符将由数据库目录名称决定。您可以使用jdbcEnvironment更改选择条件。如果你放置任何条件选项文本将是属性值。
应用程序属性
spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=password
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
spring.jpa.show-sql=true
spring.jpa.hibernate.naming.physical-strategy=com.example.demo.DynamicPhysicalNamingStrategy
# dynamic
user.table.name=TESTDB:TestUser,TESTDB2:TestUser2
user.column.name=username
用户实体
@Table(name = "${user.table.name}")
@Entity
@Data
public class User {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;
@Column(name = "${user.column.name}")
private String name;
private String email;
}
动态物理命名策略
package com.example.demo;
import org.hibernate.boot.model.naming.Identifier;
import org.hibernate.boot.model.naming.PhysicalNamingStrategy;
import org.hibernate.engine.jdbc.env.spi.JdbcEnvironment;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.core.env.Environment;
import org.springframework.stereotype.Component;
import org.springframework.util.Assert;
import java.util.Locale;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* It is copied from {@link org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl}
*/
@Component
public class DynamicPhysicalNamingStrategy implements PhysicalNamingStrategy, ApplicationContextAware {
private final Pattern VALUE_PATTERN = Pattern.compile("^\$\{([\w.]+)}$");
private Environment environment;
@Override
public Identifier toPhysicalCatalogName(Identifier name, JdbcEnvironment jdbcEnvironment) {
return apply(name, jdbcEnvironment);
}
@Override
public Identifier toPhysicalSchemaName(Identifier name, JdbcEnvironment jdbcEnvironment) {
return apply(name, jdbcEnvironment);
}
@Override
public Identifier toPhysicalTableName(Identifier name, JdbcEnvironment jdbcEnvironment) {
return apply(name, jdbcEnvironment);
}
@Override
public Identifier toPhysicalSequenceName(Identifier name, JdbcEnvironment jdbcEnvironment) {
return apply(name, jdbcEnvironment);
}
@Override
public Identifier toPhysicalColumnName(Identifier name, JdbcEnvironment jdbcEnvironment) {
return apply(name, jdbcEnvironment);
}
private Identifier apply(Identifier name, JdbcEnvironment jdbcEnvironment) {
if (name == null) {
return null;
}
// Custom Implementation Start
String text = name.getText();
Matcher matcher = VALUE_PATTERN.matcher(text);
if (matcher.matches()) {
String propertyKey = matcher.group(1);
text = environment.getProperty(propertyKey);
Assert.notNull(text, "Property is not found '" + propertyKey + "'");
// extract catalog selection part
// Example:
// Current Catalog: TESTDB
// Property: TESTDB:TestUser, TESTDB2:TestUser
// Text will be TestUser
Pattern catalogPattern = Pattern.compile(jdbcEnvironment.getCurrentCatalog().getText() + ":([^,]+)");
Matcher catalogMatcher = catalogPattern.matcher(text);
if (catalogMatcher.find()) {
text = catalogMatcher.group(1);
}
// Caution: You can remove below return function, if so text will be transformed with spring advice
return getIdentifier(text, name.isQuoted(), jdbcEnvironment);
}
// Custom Implementation End
StringBuilder builder = new StringBuilder(text.replace('.', '_'));
for (int i = 1; i < builder.length() - 1; i++) {
if (isUnderscoreRequired(builder.charAt(i - 1), builder.charAt(i), builder.charAt(i + 1))) {
builder.insert(i++, '_');
}
}
return getIdentifier(builder.toString(), name.isQuoted(), jdbcEnvironment);
}
/**
* Get an identifier for the specified details. By default this method will return an
* identifier with the name adapted based on the result of
* {@link #isCaseInsensitive(JdbcEnvironment)}
*
* @param name the name of the identifier
* @param quoted if the identifier is quoted
* @param jdbcEnvironment the JDBC environment
* @return an identifier instance
*/
protected Identifier getIdentifier(String name, boolean quoted, JdbcEnvironment jdbcEnvironment) {
if (isCaseInsensitive(jdbcEnvironment)) {
name = name.toLowerCase(Locale.ROOT);
}
return new Identifier(name, quoted);
}
/**
* Specify whether the database is case sensitive.
*
* @param jdbcEnvironment the JDBC environment which can be used to determine case
* @return true if the database is case insensitive sensitivity
*/
protected boolean isCaseInsensitive(JdbcEnvironment jdbcEnvironment) {
return true;
}
private boolean isUnderscoreRequired(char before, char current, char after) {
return Character.isLowerCase(before) && Character.isUpperCase(current) && Character.isLowerCase(after);
}
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
environment = applicationContext.getBean(Environment.class);
}
}
测试
package com.example.demo;
import com.example.demo.entity.User;
import com.example.demo.repository.UserRepository;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
@SpringBootTest
class DemoApplicationTests {
@Autowired
private UserRepository userRepository;
@Test
void contextLoads() {
User user = new User();
user.setName("test");
user.setEmail("test@test.com");
userRepository.save(user);
userRepository.findAll();
}
}
Hibernate: call next value for hibernate_sequence
Hibernate: insert into testuser (email, username, id) values (?, ?, ?)
Hibernate: select user0_.id as id1_0_, user0_.email as email2_0_, user0_.username as username3_0_ from testuser user0_