Springboot集成sqlite数据库，并使用jpa、Hibernate操作sqlite

之前举例使用jpa、Hibernate多是以mysql为例，这次因为需要使用一个内嵌式数据库，选择了sqlite，网上多是讲一些sqlite的api封装的框架。这里我们还是使用jpa、Hibernate来操作sqlite。

新建一个Springboot项目，pom如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.mindata.blockchain</groupId>
	<artifactId>md_blockchain</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>md_blockchain</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.10.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
		<fastjson.version>1.2.29</fastjson.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		
		<dependency>
			<groupId>com.alibaba</groupId>
			<artifactId>fastjson</artifactId>
			<version>${fastjson.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>
        <dependency>
            <groupId>org.xerial</groupId>
            <artifactId>sqlite-jdbc</artifactId>
            <version>3.20.0</version>
        </dependency>
		<!-- 用于配置数据源 -->
		<dependency>
			<groupId>org.apache.commons</groupId>
			<artifactId>commons-dbcp2</artifactId>
			<version>2.1.1</version>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>


</project>

要使用sqlite，需要引入sqlite-jdbc这个依赖。

然后需要配置数据源DataSource，见DataSourceConfiguration.java

package com.mindata.blockchain.core.sqlite;

import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.sqlite.SQLiteDataSource;

import javax.sql.DataSource;


/**
 * 配置sqlite数据库的DataSource
 * @author wuweifeng wrote on 2018/3/2.
 */
@Configuration
public class DataSourceConfiguration {

    @Bean(destroyMethod = "", name = "EmbeddeddataSource")
    public DataSource dataSource() {
        DataSourceBuilder dataSourceBuilder = DataSourceBuilder.create();
        dataSourceBuilder.driverClassName("org.sqlite.JDBC");
        dataSourceBuilder.url("jdbc:sqlite:" + "example.db");
        dataSourceBuilder.type(SQLiteDataSource.class);
        return dataSourceBuilder.build();
    }

}

这里的配置也可以写在application.yml里，加载driverClass驱动，设置数据库名为example.db。名字可以自己设置，注意，使用时不需要手工创建example.db，它会自动创建的。

然后配置Jpa相关，JpaConfiguration.java

package com.mindata.blockchain.core.sqlite;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.annotation.Resource;
import javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;
import java.util.Map;

/**
 * @author wuweifeng wrote on 2018/3/2.
 */
@Configuration
@EnableJpaRepositories(
        basePackages = "com.mindata.blockchain.core.repository",
        transactionManagerRef = "jpaTransactionManager",
        entityManagerFactoryRef = "localContainerEntityManagerFactoryBean"
)
@EnableTransactionManagement
public class JpaConfiguration {
    @Resource
    private JpaProperties jpaProperties;

    @Autowired
    @Bean
    public JpaTransactionManager jpaTransactionManager(@Qualifier(value = "EmbeddeddataSource") DataSource
                                                               dataSource, EntityManagerFactory
                                                               entityManagerFactory) {
        JpaTransactionManager jpaTransactionManager
                = new JpaTransactionManager();
        jpaTransactionManager.setEntityManagerFactory(entityManagerFactory);
        jpaTransactionManager.setDataSource(dataSource);

        return jpaTransactionManager;
    }

    @Autowired
    @Bean
    LocalContainerEntityManagerFactoryBean localContainerEntityManagerFactoryBean(@Qualifier(value =
            "EmbeddeddataSource") DataSource dataSource, EntityManagerFactoryBuilder builder) {
        return builder.dataSource(dataSource)
                .packages("com.mindata.blockchain.core.model")
                .properties(getVendorProperties(dataSource))
                .build();
    }

    private Map<String, String> getVendorProperties(DataSource dataSource) {
        return jpaProperties.getHibernateProperties(dataSource);
    }

}

这个类和之前使用mysql时配置的jpa并没有什么区别，basePackages里是Repository的目录，下面构建LocalContainerEntityManagerFactoryBean时是model的目录。和配置mysql完全一样。然后Autowired JpaProperties，这个jpaProperties就是在yml配置的各属性，在debug时，可以看到里面的属性。

所以我们的application.yml是

spring:
  jpa:
    show-sql: false
    database-platform: com.mindata.blockchain.core.sqlite.SQLiteDialect
    generate-ddl: true

和mysql唯一的不同就是这个database-platform，需要指明为SQLiteDialect即SQLite方言。

可以看到这个类是自定义的，spring官方没有提供这个方言。

如果你用的是Hibernate4，那么可以在这个地址https://github.com/EnigmaBridge/hibernate4-sqlite-dialect 找到Hibernate4-sqlite，直接添加依赖就好。我们使用的是Hibernate5，需要添加如下几个类，设置对应的Hibernate5对sqlite的方言。

SQLiteDialect.java

package com.mindata.blockchain.core.sqlite;

import com.mindata.blockchain.core.sqlite.identity.SQLiteDialectIdentityColumnSupport;
import org.hibernate.JDBCException;
import org.hibernate.ScrollMode;
import org.hibernate.dialect.Dialect;
import org.hibernate.dialect.function.*;
import org.hibernate.dialect.identity.IdentityColumnSupport;
import org.hibernate.dialect.pagination.AbstractLimitHandler;
import org.hibernate.dialect.pagination.LimitHandler;
import org.hibernate.dialect.pagination.LimitHelper;
import org.hibernate.dialect.unique.DefaultUniqueDelegate;
import org.hibernate.dialect.unique.UniqueDelegate;
import org.hibernate.engine.spi.RowSelection;
import org.hibernate.exception.DataException;
import org.hibernate.exception.JDBCConnectionException;
import org.hibernate.exception.LockAcquisitionException;
import org.hibernate.exception.spi.SQLExceptionConversionDelegate;
import org.hibernate.exception.spi.TemplatedViolatedConstraintNameExtracter;
import org.hibernate.exception.spi.ViolatedConstraintNameExtracter;
import org.hibernate.internal.util.JdbcExceptionHelper;
import org.hibernate.mapping.Column;
import org.hibernate.type.StandardBasicTypes;

import java.sql.SQLException;
import java.sql.Types;

/**
 * @author wuweifeng wrote on 2018/3/2.
 */
public class SQLiteDialect extends Dialect {
    private final UniqueDelegate uniqueDelegate;

    public SQLiteDialect() {
        registerColumnType(Types.BIT, "boolean");
        //registerColumnType(Types.FLOAT, "float");
        //registerColumnType(Types.DOUBLE, "double");
        registerColumnType(Types.DECIMAL, "decimal");
        registerColumnType(Types.CHAR, "char");
        registerColumnType(Types.LONGVARCHAR, "longvarchar");
        registerColumnType(Types.TIMESTAMP, "datetime");
        registerColumnType(Types.BINARY, "blob");
        registerColumnType(Types.VARBINARY, "blob");
        registerColumnType(Types.LONGVARBINARY, "blob");

        registerFunction("concat", new VarArgsSQLFunction(StandardBasicTypes.STRING, "", "||", ""));
        registerFunction("mod", new SQLFunctionTemplate(StandardBasicTypes.INTEGER, "?1 % ?2"));
        registerFunction("quote", new StandardSQLFunction("quote", StandardBasicTypes.STRING));
        registerFunction("random", new NoArgSQLFunction("random", StandardBasicTypes.INTEGER));
        registerFunction("round", new StandardSQLFunction("round"));
        registerFunction("substr", new StandardSQLFunction("substr", StandardBasicTypes.STRING));
        registerFunction("trim", new AbstractAnsiTrimEmulationFunction() {
            @Override
            protected SQLFunction resolveBothSpaceTrimFunction() {
                return new SQLFunctionTemplate(StandardBasicTypes.STRING, "trim(?1)");
            }

            @Override
            protected SQLFunction resolveBothSpaceTrimFromFunction() {
                return new SQLFunctionTemplate(StandardBasicTypes.STRING, "trim(?2)");
            }

            @Override
            protected SQLFunction resolveLeadingSpaceTrimFunction() {
                return new SQLFunctionTemplate(StandardBasicTypes.STRING, "ltrim(?1)");
            }

            @Override
            protected SQLFunction resolveTrailingSpaceTrimFunction() {
                return new SQLFunctionTemplate(StandardBasicTypes.STRING, "rtrim(?1)");
            }

            @Override
            protected SQLFunction resolveBothTrimFunction() {
                return new SQLFunctionTemplate(StandardBasicTypes.STRING, "trim(?1, ?2)");
            }

            @Override
            protected SQLFunction resolveLeadingTrimFunction() {
                return new SQLFunctionTemplate(StandardBasicTypes.STRING, "ltrim(?1, ?2)");
            }

            @Override
            protected SQLFunction resolveTrailingTrimFunction() {
                return new SQLFunctionTemplate(StandardBasicTypes.STRING, "rtrim(?1, ?2)");
            }
        });
        uniqueDelegate = new SQLiteUniqueDelegate(this);
    }

    // database type mapping support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	/*@Override
	public String getCastTypeName(int code) {
		// http://sqlite.org/lang_expr.html#castexpr
		return super.getCastTypeName( code );
	}*/

    // IDENTITY support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    private static final SQLiteDialectIdentityColumnSupport IDENTITY_COLUMN_SUPPORT = new
            SQLiteDialectIdentityColumnSupport(new SQLiteDialect());


    @Override
    public IdentityColumnSupport getIdentityColumnSupport() {
        return IDENTITY_COLUMN_SUPPORT;
    }

    // limit/offset support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    private static final AbstractLimitHandler LIMIT_HANDLER = new AbstractLimitHandler() {
        @Override
        public String processSql(String sql, RowSelection selection) {
            final boolean hasOffset = LimitHelper.hasFirstRow(selection);
            return sql + (hasOffset ? " limit ? offset ?" : " limit ?");
        }

        @Override
        public boolean supportsLimit() {
            return true;
        }

        @Override
        public boolean bindLimitParametersInReverseOrder() {
            return true;
        }
    };

    @Override
    public LimitHandler getLimitHandler() {
        return LIMIT_HANDLER;
    }

    // lock acquisition support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    @Override
    public boolean supportsLockTimeouts() {
        // may be http://sqlite.org/c3ref/db_mutex.html ?
        return false;
    }

    @Override
    public String getForUpdateString() {
        return "";
    }

    @Override
    public boolean supportsOuterJoinForUpdate() {
        return false;
    }

    // current timestamp support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    @Override
    public boolean supportsCurrentTimestampSelection() {
        return true;
    }

    @Override
    public boolean isCurrentTimestampSelectStringCallable() {
        return false;
    }

    @Override
    public String getCurrentTimestampSelectString() {
        return "select current_timestamp";
    }

    // SQLException support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    private static final int SQLITE_BUSY = 5;
    private static final int SQLITE_LOCKED = 6;
    private static final int SQLITE_IOERR = 10;
    private static final int SQLITE_CORRUPT = 11;
    private static final int SQLITE_NOTFOUND = 12;
    private static final int SQLITE_FULL = 13;
    private static final int SQLITE_CANTOPEN = 14;
    private static final int SQLITE_PROTOCOL = 15;
    private static final int SQLITE_TOOBIG = 18;
    private static final int SQLITE_CONSTRAINT = 19;
    private static final int SQLITE_MISMATCH = 20;
    private static final int SQLITE_NOTADB = 26;

    @Override
    public SQLExceptionConversionDelegate buildSQLExceptionConversionDelegate() {
        return new SQLExceptionConversionDelegate() {
            @Override
            public JDBCException convert(SQLException sqlException, String message, String sql) {
                final int errorCode = JdbcExceptionHelper.extractErrorCode(sqlException) & 0xFF;
                if (errorCode == SQLITE_TOOBIG || errorCode == SQLITE_MISMATCH) {
                    return new DataException(message, sqlException, sql);
                } else if (errorCode == SQLITE_BUSY || errorCode == SQLITE_LOCKED) {
                    return new LockAcquisitionException(message, sqlException, sql);
                } else if ((errorCode >= SQLITE_IOERR && errorCode <= SQLITE_PROTOCOL) || errorCode == SQLITE_NOTADB) {
                    return new JDBCConnectionException(message, sqlException, sql);
                }

                // returning null allows other delegates to operate
                return null;
            }
        };
    }

    @Override
    public ViolatedConstraintNameExtracter getViolatedConstraintNameExtracter() {
        return EXTRACTER;
    }

    private static final ViolatedConstraintNameExtracter EXTRACTER = new TemplatedViolatedConstraintNameExtracter() {
        @Override
        protected String doExtractConstraintName(SQLException sqle) throws NumberFormatException {
            final int errorCode = JdbcExceptionHelper.extractErrorCode(sqle) & 0xFF;
            if (errorCode == SQLITE_CONSTRAINT) {
                return extractUsingTemplate("constraint ", " failed", sqle.getMessage());
            }
            return null;
        }
    };

    // union subclass support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    @Override
    public boolean supportsUnionAll() {
        return true;
    }

    // DDL support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    @Override
    public boolean canCreateSchema() {
        return false;
    }

    @Override
    public boolean hasAlterTable() {
        // As specified in NHibernate dialect
        return false;
    }

    @Override
    public boolean dropConstraints() {
        return false;
    }

    @Override
    public boolean qualifyIndexName() {
        return false;
    }

    @Override
    public String getAddColumnString() {
        return "add column";
    }

    @Override
    public String getDropForeignKeyString() {
        throw new UnsupportedOperationException("No drop foreign key syntax supported by SQLiteDialect");
    }

    @Override
    public String getAddForeignKeyConstraintString(String constraintName,
                                                   String[] foreignKey, String referencedTable, String[] primaryKey,
                                                   boolean referencesPrimaryKey) {
        throw new UnsupportedOperationException("No add foreign key syntax supported by SQLiteDialect");
    }

    @Override
    public String getAddPrimaryKeyConstraintString(String constraintName) {
        throw new UnsupportedOperationException("No add primary key syntax supported by SQLiteDialect");
    }

    @Override
    public boolean supportsCommentOn() {
        return true;
    }

    @Override
    public boolean supportsIfExistsBeforeTableName() {
        return true;
    }

  /* not case insensitive for unicode characters by default (ICU extension needed)
	public boolean supportsCaseInsensitiveLike() {
    return true;
  }
  */

    @Override
    public boolean doesReadCommittedCauseWritersToBlockReaders() {
        // TODO Validate (WAL mode...)
        return true;
    }

    @Override
    public boolean doesRepeatableReadCauseReadersToBlockWriters() {
        return true;
    }

    @Override
    public boolean supportsTupleDistinctCounts() {
        return false;
    }

    @Override
    public int getInExpressionCountLimit() {
        // Compile/runtime time option: http://sqlite.org/limits.html#max_variable_number
        return 1000;
    }

    @Override
    public UniqueDelegate getUniqueDelegate() {
        return uniqueDelegate;
    }

    private static class SQLiteUniqueDelegate extends DefaultUniqueDelegate {
        public SQLiteUniqueDelegate(Dialect dialect) {
            super(dialect);
        }

        @Override
        public String getColumnDefinitionUniquenessFragment(Column column) {
            return " unique";
        }
    }

    @Override
    public String getSelectGUIDString() {
        return "select hex(randomblob(16))";
    }

    @Override
    public ScrollMode defaultScrollMode() {
        return ScrollMode.FORWARD_ONLY;
    }
}

package com.mindata.blockchain.core.sqlite;

import org.hibernate.boot.MetadataBuilder;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.spi.MetadataBuilderInitializer;
import org.hibernate.engine.jdbc.dialect.internal.DialectResolverSet;
import org.hibernate.engine.jdbc.dialect.spi.DialectResolver;
import org.jboss.logging.Logger;

/**
 * SQLite工具
 */
public class SQLiteMetadataBuilderInitializer implements MetadataBuilderInitializer {

    private final static Logger logger = Logger.getLogger(SQLiteMetadataBuilderInitializer.class);

    @Override
    public void contribute(MetadataBuilder metadataBuilder, StandardServiceRegistry serviceRegistry) {
        DialectResolver dialectResolver = serviceRegistry.getService(DialectResolver.class);

        if (!(dialectResolver instanceof DialectResolverSet)) {
            logger.warnf("DialectResolver '%s' is not an instance of DialectResolverSet, not registering SQLiteDialect",
                    dialectResolver);
            return;
        }

        ((DialectResolverSet) dialectResolver).addResolver(resolver);
    }

    static private final SQLiteDialect dialect = new SQLiteDialect();

    static private final DialectResolver resolver = (DialectResolver) info -> {
        if (info.getDatabaseName().equals("SQLite")) {
            return dialect;
        }

        return null;
    };
}

package com.mindata.blockchain.core.sqlite.identity;

import org.hibernate.dialect.Dialect;
import org.hibernate.dialect.identity.IdentityColumnSupportImpl;

/**
 * @author wuweifeng wrote on 2018/3/2.
 */
public class SQLiteDialectIdentityColumnSupport extends IdentityColumnSupportImpl {
    public SQLiteDialectIdentityColumnSupport(Dialect dialect) {
        super(dialect);
    }

    @Override
    public boolean supportsIdentityColumns() {
        return true;
    }

  /*
	public boolean supportsInsertSelectIdentity() {
    return true; // As specified in NHibernate dialect
  }
  */

    @Override
    public boolean hasDataTypeInIdentityColumn() {
        // As specified in NHibernate dialect
        // FIXME true
        return false;
    }

  /*
	public String appendIdentitySelectToInsert(String insertString) {
    return new StringBuffer(insertString.length()+30). // As specified in NHibernate dialect
      append(insertString).
      append("; ").append(getIdentitySelectString()).
      toString();
  }
  */

    @Override
    public String getIdentitySelectString(String table, String column, int type) {
        return "select last_insert_rowid()";
    }

    @Override
    public String getIdentityColumnString(int type) {
        // return "integer primary key autoincrement";
        // FIXME "autoincrement"
        return "integer";
    }
}

以上设置完毕就结束了。

然后你就可以在自己设置的model、Repository文件夹里添加自己的model类和Repository类，就和操作mysql一样，来享受Jpa带来的便捷吧。