java - org.hibernate.MappingException : No Dialect mapping for JDBC type: 2000

Question

我正在尝试将表的一列映射到 JSONUserType。

我有模型:

@Entity
@TypeDefs({ @TypeDef(name = "JSONUserType", typeClass = JSONUserType.class) })
@Table( name = "my_table")
public class MyClass {
....
.....
@Column(name = "permissions")
@Type(type = "JSONUserType", parameters = { @Parameter(name = "classType", 
value = "java.util.HashMap") })
private Map<String, Boolean> permissions;
......
......
Getter and setter
.....
.....
}

我已经实现了 JSONUserType:

package it......model;

import java.io.IOException;
import java.io.Serializable;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;
import java.text.SimpleDateFormat;
import java.util.Collection;
import java.util.Objects;
import java.util.Properties;

import org.hibernate.HibernateException;
import org.hibernate.engine.spi.SharedSessionContractImplementor;
import org.hibernate.internal.util.ReflectHelper;
import org.hibernate.usertype.ParameterizedType;
import org.hibernate.usertype.UserType;

import com.fasterxml.jackson.annotation.JsonInclude.Include;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * Hibernate {@link UserType} implementation to handle JSON objects
 *
 * @see https://docs.jboss.org/hibernate/orm/4.1/javadocs/org/hibernate/usertype/ UserType.html
 */
public class JSONUserType implements UserType, ParameterizedType, Serializable {

    private static final long serialVersionUID = 1L;

    private static final ObjectMapper MAPPER = new ObjectMapper()
    // do NOT serialize null properties
    .setSerializationInclusion(Include.NON_NULL)
    // serialize dates using ISO format instead of epoch time
    .setDateFormat(new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'"));

    private static final String CLASS_TYPE = "classType";
    private static final String COLLECTION_CLASS_TYPE = "collectionClassType";

    private static final int[] SQL_TYPES = new int[] { Types.JAVA_OBJECT };

    private Class<?> classType;
    private Class<?> collectionClassType;
    private int sqlType = Types.LONGVARCHAR; // before any guessing

    @Override
    public void setParameterValues(Properties params) {

        // Retrieve the class name from params
        String classTypeName = params.getProperty(CLASS_TYPE);
        try {
            // Retrieve the classType by reflection
            classType = ReflectHelper.classForName(classTypeName, this.getClass());
            // If class is a collection, we may have to retrieve the classType of its elements
            if (Collection.class.isAssignableFrom(classType)) {
                // Retrieve the elements class name from params
                String collectionClassTypeName = params.getProperty(COLLECTION_CLASS_TYPE);
                if (collectionClassTypeName != null) {
                    try {
                        // Retrieve the elements classType by reflection
                        collectionClassType = ReflectHelper.classForName(collectionClassTypeName, this.getClass());
                    }
                    catch (ClassNotFoundException e) {
                        throw new HibernateException("collectionClassType not found : " + collectionClassTypeName, e);
                    }
                }
            }
        }
        catch (ClassNotFoundException e) {
            throw new HibernateException("classType not found : " + classTypeName, e);
        }

        sqlType = Types.OTHER;

    }

    @Override
    public Object assemble(Serializable cached, Object owner) throws HibernateException {

        return deepCopy(cached);
    }

    @Override
    public Object deepCopy(Object value) throws HibernateException {

        Object copy = null;
        if (value != null) {

            try {
                return MAPPER.readValue(MAPPER.writeValueAsString(value), classType);
            }
            catch (IOException e) {
                throw new HibernateException("unable to deep copy object", e);
            }
        }
        return copy;
    }

    @Override
    public Serializable disassemble(Object value) throws HibernateException {

        try {
            return MAPPER.writeValueAsString(value);
        }
        catch (JsonProcessingException e) {
            throw new HibernateException("unable to disassemble object", e);
        }
    }

    @Override
    public boolean equals(Object x, Object y) throws HibernateException {

        if (x == null && y == null) return true;
        if (x == null) return false;
        if (y == null) return false;

        try {
            return MAPPER.writeValueAsString(x).equals(MAPPER.writeValueAsString(y));
        }
        catch (JsonProcessingException e) {
        }
        return false;
    }

    @Override
    public int hashCode(Object x) throws HibernateException {

        return Objects.hash(x);
    }

    @Override
    public boolean isMutable() {

        return true;
    }

    @Override
    public Object nullSafeGet(ResultSet rs, String[] names, SharedSessionContractImplementor session, Object owner) throws HibernateException, SQLException {

        if (rs.getString(names[0]) == null) return null;

        Object obj = null;
        try {
            // If we have defined a class type for the collection elements, cast JSON string to Collection<collectionClassType>
            if (collectionClassType != null) {
                obj = MAPPER.readValue(rs.getString(names[0]), MAPPER.getTypeFactory().constructCollectionType((Class<? extends Collection>) classType, collectionClassType));
            }
            // Else simply cast JSON string to classType
            else {
                obj = MAPPER.readValue(rs.getString(names[0]), classType);
            }
        }
        catch (IOException e) {
            throw new HibernateException("unable to read object from result set", e);
        }
        return obj;
    }

    @Override
    public void nullSafeSet(PreparedStatement st, Object value, int index, SharedSessionContractImplementor session) throws HibernateException, SQLException {

        if (value == null) {
            st.setNull(index, sqlType);
        } else {
            try {
                st.setObject(index, MAPPER.writeValueAsString(value), sqlType);
            }
            catch (JsonProcessingException e) {
                throw new HibernateException("unable to set object to result set", e);
            }
        }
    }

    @Override
    public Object replace(Object original, Object target, Object owner) throws HibernateException {

        return deepCopy(original);
    }

    @Override
    public Class<?> returnedClass() {

        return classType;
    }

    @Override
    public int[] sqlTypes() {

        return SQL_TYPES;
    }
}

然后我有:

<tx:annotation-driven transaction-manager="transactionManager" />

<bean id="transactionManager" 
class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>

<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="persistenceUnitName" value="persistenceUnit" />
    <property name="dataSource" ref="dataSource" />
    <property name="packagesToScan" value="it.oandsi" />
    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
    </property>
    <property name="jpaProperties">
        <props>
            <prop key="hibernate.dialect">${hibernate.dialect}</prop>
            <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
            <prop key="hibernate.format_sql">${hibernate.format_sql}</prop>
            <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
        </props>
    </property> 
</bean>

其中 hibernate.dialect 是 org.hibernate.dialect.MySQL5InnoDBDialect

当我启动 tomcat 时，出现错误“org.hibernate.MappingException:没有 JDBC 类型的方言映射:2000”

这里是堆栈跟踪:

Caused by: org.hibernate.MappingException: No Dialect mapping for JDBC type: 2000
at org.hibernate.dialect.TypeNames.get(TypeNames.java:70)
at org.hibernate.dialect.TypeNames.get(TypeNames.java:101)
at org.hibernate.dialect.Dialect.getTypeName(Dialect.java:346)
at org.hibernate.mapping.Column.getSqlType(Column.java:231)
at org.hibernate.mapping.Table.sqlAlterStrings(Table.java:473)
at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.migrateTable(AbstractSchemaMigrator.java:295)
at org.hibernate.tool.schema.internal.GroupedSchemaMigratorImpl.performTablesMigration(GroupedSchemaMigratorImpl.java:75)
at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.performMigration(AbstractSchemaMigrator.java:203)
at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.doMigration(AbstractSchemaMigrator.java:110)
at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.performDatabaseAction(SchemaManagementToolCoordinator.java:183)
at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.process(SchemaManagementToolCoordinator.java:72)
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:309)
at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:452)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:889)

请问你能帮我吗？

Answer 1

您需要扩展MySQL5InnoDBDialect方言并提供映射。这就像将以下构造函数添加到自定义类一样简单(前提是您已经配置了用户类型和其他类型)。

public MyCustomDialect() {
    super();
    this.registerColumnType(Types.JAVA_OBJECT, "json"); // JAVA_OBJECT = 2000
}