https://github.com/spring-projects/spring-framework: Spring JDBC (Spring IO)
  • Juergen Hoeller 
/*
 * Copyright 2002-2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.jdbc.core.support;

import java.io.InputStream;
import java.io.Reader;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Types;

import org.springframework.jdbc.core.DisposableSqlTypeValue;
import org.springframework.jdbc.support.lob.DefaultLobHandler;
import org.springframework.jdbc.support.lob.LobCreator;
import org.springframework.jdbc.support.lob.LobHandler;
import org.springframework.lang.Nullable;


Object to represent an SQL BLOB/CLOB value parameter. BLOBs can either be an
InputStream or a byte array. CLOBs can be in the form of a Reader, InputStream
or String. Each CLOB/BLOB value will be stored together with its length.
The type is based on which constructor is used. Objects of this class are
immutable except for the LobCreator reference. Use them and discard them.

This class holds a reference to a LocCreator that must be closed after the
update has completed. This is done via a call to the closeLobCreator method.
All handling of the LobCreator is done by the framework classes that use it -
no need to set or close the LobCreator for end users of this class.

A usage example:

JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);  // reusable object
LobHandler lobHandler = new DefaultLobHandler();  // reusable object
jdbcTemplate.update(
    "INSERT INTO imagedb (image_name, content, description) VALUES (?, ?, ?)",
    new Object[] {
      name,
      new SqlLobValue(contentStream, contentLength, lobHandler),
      new SqlLobValue(description, lobHandler)
    },
    new int[] {Types.VARCHAR, Types.BLOB, Types.CLOB});



Author:Thomas Risberg, Juergen Hoeller
See Also:
Since:1.1
/**
 * Object to represent an SQL BLOB/CLOB value parameter. BLOBs can either be an
 * InputStream or a byte array. CLOBs can be in the form of a Reader, InputStream
 * or String. Each CLOB/BLOB value will be stored together with its length.
 * The type is based on which constructor is used. Objects of this class are
 * immutable except for the LobCreator reference. Use them and discard them.
 *
 * <p>This class holds a reference to a LocCreator that must be closed after the
 * update has completed. This is done via a call to the closeLobCreator method.
 * All handling of the LobCreator is done by the framework classes that use it -
 * no need to set or close the LobCreator for end users of this class.
 *
 * <p>A usage example:
 *
 * <pre class="code">JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);  // reusable object
 * LobHandler lobHandler = new DefaultLobHandler();  // reusable object
 *
 * jdbcTemplate.update(
 *     "INSERT INTO imagedb (image_name, content, description) VALUES (?, ?, ?)",
 *     new Object[] {
 *       name,
 *       new SqlLobValue(contentStream, contentLength, lobHandler),
 *       new SqlLobValue(description, lobHandler)
 *     },
 *     new int[] {Types.VARCHAR, Types.BLOB, Types.CLOB});
 * </pre>
 *
 * @author Thomas Risberg
 * @author Juergen Hoeller
 * @since 1.1
 * @see org.springframework.jdbc.support.lob.LobHandler
 * @see org.springframework.jdbc.support.lob.LobCreator
 * @see org.springframework.jdbc.core.JdbcTemplate#update(String, Object[], int[])
 * @see org.springframework.jdbc.object.SqlUpdate#update(Object[])
 * @see org.springframework.jdbc.object.StoredProcedure#execute(java.util.Map)
 */
public class SqlLobValue implements DisposableSqlTypeValue {

	@Nullable
	private final Object content;

	private final int length;

	
This contains a reference to the LobCreator - so we can close it
once the update is done.

/**
	 * This contains a reference to the LobCreator - so we can close it
	 * once the update is done.
	 */
	private final LobCreator lobCreator;


	
Create a new BLOB value with the given byte array,
using a DefaultLobHandler.

Params:
  • bytes – the byte array containing the BLOB value
See Also:
/**
	 * Create a new BLOB value with the given byte array,
	 * using a DefaultLobHandler.
	 * @param bytes the byte array containing the BLOB value
	 * @see org.springframework.jdbc.support.lob.DefaultLobHandler
	 */
	public SqlLobValue(@Nullable byte[] bytes) {
		this(bytes, new DefaultLobHandler());
	}

	
Create a new BLOB value with the given byte array.

Params:
  • bytes – the byte array containing the BLOB value
  • lobHandler – the LobHandler to be used
/**
	 * Create a new BLOB value with the given byte array.
	 * @param bytes the byte array containing the BLOB value
	 * @param lobHandler the LobHandler to be used
	 */
	public SqlLobValue(@Nullable byte[] bytes, LobHandler lobHandler) {
		this.content = bytes;
		this.length = (bytes != null ? bytes.length : 0);
		this.lobCreator = lobHandler.getLobCreator();
	}

	
Create a new CLOB value with the given content string,
using a DefaultLobHandler.

Params:
  • content – the String containing the CLOB value
See Also:
/**
	 * Create a new CLOB value with the given content string,
	 * using a DefaultLobHandler.
	 * @param content the String containing the CLOB value
	 * @see org.springframework.jdbc.support.lob.DefaultLobHandler
	 */
	public SqlLobValue(@Nullable String content) {
		this(content, new DefaultLobHandler());
	}

	
Create a new CLOB value with the given content string.

Params:
  • content – the String containing the CLOB value
  • lobHandler – the LobHandler to be used
/**
	 * Create a new CLOB value with the given content string.
	 * @param content the String containing the CLOB value
	 * @param lobHandler the LobHandler to be used
	 */
	public SqlLobValue(@Nullable String content, LobHandler lobHandler) {
		this.content = content;
		this.length = (content != null ? content.length() : 0);
		this.lobCreator = lobHandler.getLobCreator();
	}

	
Create a new BLOB/CLOB value with the given stream,
using a DefaultLobHandler.

Params:
  • stream – the stream containing the LOB value
  • length – the length of the LOB value
See Also:
/**
	 * Create a new BLOB/CLOB value with the given stream,
	 * using a DefaultLobHandler.
	 * @param stream the stream containing the LOB value
	 * @param length the length of the LOB value
	 * @see org.springframework.jdbc.support.lob.DefaultLobHandler
	 */
	public SqlLobValue(InputStream stream, int length) {
		this(stream, length, new DefaultLobHandler());
	}

	
Create a new BLOB/CLOB value with the given stream.

Params:
  • stream – the stream containing the LOB value
  • length – the length of the LOB value
  • lobHandler – the LobHandler to be used
/**
	 * Create a new BLOB/CLOB value with the given stream.
	 * @param stream the stream containing the LOB value
	 * @param length the length of the LOB value
	 * @param lobHandler the LobHandler to be used
	 */
	public SqlLobValue(InputStream stream, int length, LobHandler lobHandler) {
		this.content = stream;
		this.length = length;
		this.lobCreator = lobHandler.getLobCreator();
	}

	
Create a new CLOB value with the given character stream,
using a DefaultLobHandler.

Params:
  • reader – the character stream containing the CLOB value
  • length – the length of the CLOB value
See Also:
/**
	 * Create a new CLOB value with the given character stream,
	 * using a DefaultLobHandler.
	 * @param reader the character stream containing the CLOB value
	 * @param length the length of the CLOB value
	 * @see org.springframework.jdbc.support.lob.DefaultLobHandler
	 */
	public SqlLobValue(Reader reader, int length) {
		this(reader, length, new DefaultLobHandler());
	}

	
Create a new CLOB value with the given character stream.

Params:
  • reader – the character stream containing the CLOB value
  • length – the length of the CLOB value
  • lobHandler – the LobHandler to be used
/**
	 * Create a new CLOB value with the given character stream.
	 * @param reader the character stream containing the CLOB value
	 * @param length the length of the CLOB value
	 * @param lobHandler the LobHandler to be used
	 */
	public SqlLobValue(Reader reader, int length, LobHandler lobHandler) {
		this.content = reader;
		this.length = length;
		this.lobCreator = lobHandler.getLobCreator();
	}


	
Set the specified content via the LobCreator.

/**
	 * Set the specified content via the LobCreator.
	 */
	@Override
	public void setTypeValue(PreparedStatement ps, int paramIndex, int sqlType, @Nullable String typeName)
			throws SQLException {

		if (sqlType == Types.BLOB) {
			if (this.content instanceof byte[] || this.content == null) {
				this.lobCreator.setBlobAsBytes(ps, paramIndex, (byte[]) this.content);
			}
			else if (this.content instanceof String) {
				this.lobCreator.setBlobAsBytes(ps, paramIndex, ((String) this.content).getBytes());
			}
			else if (this.content instanceof InputStream) {
				this.lobCreator.setBlobAsBinaryStream(ps, paramIndex, (InputStream) this.content, this.length);
			}
			else {
				throw new IllegalArgumentException(
						"Content type [" + this.content.getClass().getName() + "] not supported for BLOB columns");
			}
		}
		else if (sqlType == Types.CLOB) {
			if (this.content instanceof String || this.content == null) {
				this.lobCreator.setClobAsString(ps, paramIndex, (String) this.content);
			}
			else if (this.content instanceof InputStream) {
				this.lobCreator.setClobAsAsciiStream(ps, paramIndex, (InputStream) this.content, this.length);
			}
			else if (this.content instanceof Reader) {
				this.lobCreator.setClobAsCharacterStream(ps, paramIndex, (Reader) this.content, this.length);
			}
			else {
				throw new IllegalArgumentException(
						"Content type [" + this.content.getClass().getName() + "] not supported for CLOB columns");
			}
		}
		else {
			throw new IllegalArgumentException("SqlLobValue only supports SQL types BLOB and CLOB");
		}
	}

	
Close the LobCreator, if any.

/**
	 * Close the LobCreator, if any.
	 */
	@Override
	public void cleanup() {
		this.lobCreator.close();
	}

}