mybatis 存取Oracle数据库中Blob类型数据

定义实体类

映射实体字段类型为String

@TableField("DATASTR")
private String datastr;

创建数据类型映射转换类

package com.zz.spxt.mapper;
import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;
import java.io.ByteArrayInputStream;
import java.io.UnsupportedEncodingException;
import java.sql.*;


/**
 * @Author: yang
 * @Date: Create in 2020/6/18
 * @Description:
 * @Modify By:
 */
public class BlobTypeHandle extends BaseTypeHandler<String> {
	private static final String DEFAULT_CHARSET = "UTF-8";
	@Override
	public void setNonNullParameter( PreparedStatement preparedStatement, int i, String s, JdbcType jdbcType ) throws SQLException
	{
		ByteArrayInputStream bis;
		try
		{
/* 把String转化成byte流 */
			bis = new ByteArrayInputStream( s.getBytes( DEFAULT_CHARSET ) );
		} catch ( UnsupportedEncodingException e )
		{
			throw new RuntimeException( "Blob Encoding Error!" );
		}
		preparedStatement.setBinaryStream( i, bis, s.length() );
	}


	@Override
	public String getNullableResult( ResultSet resultSet, String s ) throws SQLException
	{
		Blob blob = resultSet.getBlob( s );
		byte[] returnValue = null;
		String result = null;
		if ( null != blob )
		{
			returnValue = blob.getBytes( 1, (int) blob.length() );
		}
		try
		{
			if ( null != returnValue )
			{
/* 把byte转化成string */
				result = new String( returnValue, DEFAULT_CHARSET );
			}
		} catch ( UnsupportedEncodingException e )
		{
			throw new RuntimeException( "Blob Encoding Error!" );
		}
		return(result);
	}


	@Override
	public String getNullableResult( ResultSet resultSet, int i ) throws SQLException
	{
		Blob blob = resultSet.getBlob( i );
		byte[] returnValue = null;
		String result = null;
		if ( null != blob )
		{
			returnValue = blob.getBytes( 1, (int) blob.length() );
		}
		try
		{
			if ( null != returnValue )
			{
				result = new String( returnValue, DEFAULT_CHARSET );
			}
		} catch ( UnsupportedEncodingException e )
		{
			throw new RuntimeException( "Blob Encoding Error!" );
		}
		return(result);
	}


	@Override
	public String getNullableResult( CallableStatement callableStatement, int i ) throws SQLException
	{
		String	result	= null;
		Blob	blob	= callableStatement.getBlob( i );
		byte[] returnValue = null;
		if ( null != blob )
		{
			returnValue = blob.getBytes( 1, (int) blob.length() );
		}
		try
		{
/* 把byte转化成string */
			if ( null != returnValue )
			{
				result = new String( returnValue, DEFAULT_CHARSET );
			}
		} catch ( UnsupportedEncodingException e )
		{
			throw new RuntimeException( "Blob Encoding Error!" );
		}
		return(result);
	}
}

在mapper.xml 映射中指定转换类

<result column="UPDATE_DATE" property="updateDate" />
<result column="UPDATE_UID" property="updateUid" />
<result column="DATASTR" property="datastr" typeHandler="com.zz.spxt.mapper.BlobTypeHandle"/>

使用

在使用过程中按照String 类型数据操作即可，数据处理转换在自定义类中已经完成了。

参考了很多其他文章，因为这是我半夜在宿舍写的，没有记录下来引用、参考文章出处，在此非常抱歉！

有不足之处欢迎指正！