原因：java.sql.SQLException：サポートされていない文字エンコーディング 'utf8mb4'

Question

大量のutf-8エンコーディングを使用するアプリケーションを作成しています。 私はサーブレットを使用しているサーバーで、UI用にjspとjavascriptでJavaサーブレットを使用しています。
しばらく言葉を無視した後、私はutf-8エンコーディングの問題を解決することに決めました。 解決策を探しているうちに、私は<property name="hibernate.hbm2ddl.auto" value="create" />と私のまだpersistence.xmlで開発中ですので、 私は@ cosautantの答えに続いてhttps://stackoverflow.com/questions/138948/how-to-get-utf-8-working-in-java-webappsまで "MySQLデータベースとテーブル"を除いて（除外）フィルタクラスを作成しました。
それから私は、MySQLのUTF8が正確に世界のUTF-8の残りの部分ではないことを理解し、私はにpersistence.xmlでcharacterEncodingを変更：この次、また<property name="hibernate.connection.characterEncoding" value="utf8mb4" /> ：私はMySqlServerをアップグレードしhttps://mathiasbynens.be/notes/mysql-utf8mb4のリンクを、コメントを追加しました：

[クライアント] デフォルトの文字セット= utf8mb4

[mysqlの]デフォルトの文字セット= utf8mb4

[mysqldを]文字セット - クライアントハンドシェイク= FALSE文字セットサーバ= utf8mb4 c ollat​​ion-server = utf8mb4_unicode_ci

~mysql.cnf。 私はターミナルでsudo service mysql restartを入力して、MySQLを再起動し、私はmysqlのコマンドラインUIと型に行くときことを確認しました：SHOW VARIABLES WHERE Variable_name LIKE 'character\_set\_%' OR Variable_name LIKE 'collation%';この：

+--------------------------+--------------------+ 
| Variable_name   | Value    | 
+--------------------------+--------------------+ 
| character_set_client  | utf8mb4   | 
| character_set_connection | utf8mb4   | 
| character_set_database | utf8mb4   | 
| character_set_filesystem | binary    | 
| character_set_results | utf8mb4   | 
| character_set_server  | utf8mb4   | 
| character_set_system  | utf8    | 
| collation_connection  | utf8mb4_unicode_ci | 
| collation_database  | utf8mb4_unicode_ci | 
| collation_server   | utf8mb4_unicode_ci | 
+--------------------------+--------------------+ 

は私が得るものです。
またcom.mysql.jdbc_5.1.5.jarをmysql-connector-java-5.1.44-bin.jarに変更しました。

さらに、DBにアクセスしようとするたびに上記のエラーが発生します。私は私がこだわっているポイントになったと思います

Exception in thread "main" java.lang.ExceptionInInitializerError 
    at tests.Test.main(Test.java:38) 
Caused by: org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment] 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:271) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:233) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210) 
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51) 
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210) 
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352) 
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111) 
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:858) 
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:885) 
    at org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:58) 
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:55) 
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:39) 
    at utils.HibernateUtil.<clinit>(HibernateUtil.java:9) 
    ... 1 more 
Caused by: org.hibernate.exception.JDBCConnectionException: Error calling Driver#connect 
    at org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator$1$1.convert(BasicConnectionCreator.java:105) 
    at org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.convertSqlException(BasicConnectionCreator.java:123) 
    at org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:41) 
    at org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161) 
    at org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.buildPool(DriverManagerConnectionProviderImpl.java:109) 
    at org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:72) 
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210) 
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.buildJdbcConnectionAccess(JdbcEnvironmentInitiator.java:145) 
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:66) 
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35) 
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:88) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:259) 
    ... 15 more 
Caused by: java.sql.SQLException: Unsupported character encoding 'utf8mb4'. 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:897) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:886) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860) 
    at com.mysql.jdbc.ConnectionPropertiesImpl.postInitialization(ConnectionPropertiesImpl.java:2549) 
    at com.mysql.jdbc.ConnectionPropertiesImpl.initializeProperties(ConnectionPropertiesImpl.java:2519) 
    at com.mysql.jdbc.ConnectionImpl.initializeDriverProperties(ConnectionImpl.java:3140) 
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:763) 
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) 
    at sun.reflect.D Exception in thread "main" java.lang.ExceptionInInitializerError 
    at tests.Test.main(Test.java:38) 
Caused by: org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment] 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:271) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:233) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210) 
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51) 
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210) 
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352) 
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111) 
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:858) 
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:885) 
    at org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:58) 
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:55) 
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:39) 
    at utils.HibernateUtil.<clinit>(HibernateUtil.java:9) 
    ... 1 more 
Caused by: org.hibernate.exception.JDBCConnectionException: Error calling Driver#connect 
    at org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator$1$1.convert(BasicConnectionCreator.java:105) 
    at org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.convertSqlException(BasicConnectionCreator.java:123) 
    at org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:41) 
    at org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20) 
    at org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161) 
    at org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.buildPool(DriverManagerConnectionProviderImpl.java:109) 
    at org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:72) 
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210) 
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.buildJdbcConnectionAccess(JdbcEnvironmentInitiator.java:145) 
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:66) 
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35) 
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:88) 
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:259) 
    ... 15 more 
Caused by: java.sql.SQLException: Unsupported character encoding 'utf8mb4'. 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:897) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:886) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860) 
    at com.mysql.jdbc.ConnectionPropertiesImpl.postInitialization(ConnectionPropertiesImpl.java:2549) 
    at com.mysql.jdbc.ConnectionPropertiesImpl.initializeProperties(ConnectionPropertiesImpl.java:2519) 
    at com.mysql.jdbc.ConnectionImpl.initializeDriverProperties(ConnectionImpl.java:3140) 
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:763) 
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) 
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423) 
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) 
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389) 
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) 
    at org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38) 
    ... 30 moreelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423) 
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) 
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389) 
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) 
    at org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38) 
    ... 30 more 

：
が、これは私のスタックトレースです。
助けていただければ幸いです。 ありがとう！

Answer 1

HibernateのXML設定ファイルでこれを試してみてください：次のようにも接続URLに変更を加える

<property name="hibernate.connection.CharSet">utf8mb4</property> 
<property name="hibernate.connection.characterEncoding">utf8</property‌​> 
<property name="hibernate.connection.useUnicode">true</property> 

：

db.url=jdbc:mysql://localhost:3306/db_name?useUnicode=true&character_set_server=utf8mb4 

私はUTF8からutf8mb4にアップグレードするために上記の変更は十分でしたcharsetスキーム。

私は、UTF8が文字エンコードであることを明確にしたいと思いますが、UTF8MB4はMySQLがサポートする文字セットです。 UTF8MB4はUTF8のスーパーセットです。詳細については、このリンクを参照してください：https://dev.mysql.com/doc/refman/5.5/en/charset-unicode-utf8mb4.html