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BSD Licensed JDBC driver for Drizzle and MySQL
/*
* Drizzle-JDBC
*
* Copyright (c) 2009-2011, Marcus Eriksson
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following
* conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided with the distribution.
* Neither the name of the driver nor the names of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.drizzle.jdbc;
import org.drizzle.jdbc.internal.common.Utils;
import org.drizzle.jdbc.internal.SQLExceptionMapper;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Blob;
import java.sql.SQLException;
/**
* Represents a Blob.
*
* User: marcuse Date: Feb 14, 2009 Time: 9:40:54 PM
*/
public final class DrizzleBlob extends OutputStream implements Blob {
/**
* the actual blob content.
*/
private byte[] blobContent;
/**
* the size of the blob.
*/
private int actualSize;
/**
* How big the blob should be initially.
*/
private static final int INITIAL_BLOB_CONTENT_SIZE = 100;
/**
* creates an empty blob.
*/
public DrizzleBlob() {
}
/**
* creates a blob with content.
*
* @param bytes the content for the blob.
*/
public DrizzleBlob(final byte[] bytes) {
this.blobContent = bytes;
this.actualSize = bytes.length;
}
/**
* Writes the specified byte to this output stream. The general contract for write is that one byte is
* written to the output stream. The byte to be written is the eight low-order bits of the argument b.
* The 24 high-order bits of b are ignored.
*
* Subclasses of OutputStream must provide an implementation for this method.
*
* @param b the byte.
* @throws java.io.IOException if an I/O error occurs. In particular, an IOException may be thrown if
* the output stream has been closed.
*/
public void write(final int b) throws IOException {
if (this.blobContent == null) {
this.blobContent = new byte[INITIAL_BLOB_CONTENT_SIZE];
}
if (this.blobContent.length == actualSize) {
this.blobContent = Utils.copyWithLength(this.blobContent,
this.blobContent.length * 2);
}
this.blobContent[actualSize++] = (byte) b;
}
/**
* Returns the number of bytes in the BLOB value designated by this Blob object.
*
* @return length of the BLOB in bytes
* @throws java.sql.SQLException if there is an error accessing the length of the BLOB
*/
public long length() throws SQLException {
return actualSize;
}
/**
* Retrieves all or part of the BLOB value that this Blob object represents, as an array
* of bytes. This byte array contains up to length consecutive bytes starting at position
* pos.
*
* @param pos the ordinal position of the first byte in the BLOB value to be extracted; the first
* byte is at position 1
* @param length the number of consecutive bytes to be copied; the value for length must be 0 or greater
* @return a byte array containing up to length consecutive bytes from the BLOB value
* designated by this Blob object, starting with the byte at position pos
* @throws java.sql.SQLException if there is an error accessing the BLOB value; if pos is less than 1
* or length is less than 0
* @see #setBytes
* @since 1.2
*/
public byte[] getBytes(final long pos, final int length) throws SQLException {
if (pos < 1) {
throw SQLExceptionMapper.getSQLException("Pos starts at 1");
}
final int arrayPos = (int) (pos - 1);
return Utils.copyRange(blobContent, arrayPos, arrayPos + length);
}
/**
* Retrieves the BLOB value designated by this Blob instance as a stream.
*
* @return a stream containing the BLOB data
* @throws SQLException if something went wrong
* @see #setBinaryStream
*/
public InputStream getBinaryStream() throws SQLException {
return new ByteArrayInputStream(this.blobContent);
}
/**
* Retrieves the byte position at which the specified byte array pattern begins within the
* BLOB value that this Blob object represents. The search for pattern
* begins at position start.
*
* @param pattern the byte array for which to search
* @param start the position at which to begin searching; the first position is 1
* @return the position at which the pattern appears, else -1
*/
public long position(final byte[] pattern, final long start) throws SQLException {
if (start < 1) {
throw SQLExceptionMapper.getSQLException("Start should be > 0, first position is 1.");
}
if (start > actualSize) {
throw SQLExceptionMapper.getSQLException("Start should be <= " + actualSize);
}
final long actualStart = start - 1;
for (int i = (int) actualStart; i < actualSize; i++) {
if (blobContent[i] == pattern[0]) {
boolean isEqual = true;
for (int j = 1; j < pattern.length; j++) {
if (i + j >= actualSize) {
return -1;
}
if (blobContent[i + j] != pattern[j]) {
isEqual = false;
}
}
if (isEqual) {
return i + 1;
}
}
}
return -1;
}
/**
* Retrieves the byte position in the BLOB value designated by this Blob object at which
* pattern begins. The search begins at position start.
*
* @param pattern the Blob object designating the BLOB value for which to search
* @param start the position in the BLOB value at which to begin searching; the first position is 1
* @return the position at which the pattern begins, else -1
*/
public long position(final Blob pattern, final long start) throws SQLException {
return position(pattern.getBytes(1, (int) pattern.length()), start);
}
/**
* Writes the given array of bytes to the BLOB value that this Blob object represents,
* starting at position pos, and returns the number of bytes written. The array of bytes will overwrite
* the existing bytes in the Blob object starting at the position pos. If the end of the
* Blob value is reached while writing the array of bytes, then the length of the Blob
* value will be increased to accomodate the extra bytes.
*
* Note: If the value specified for pos is greater then the length+1 of the BLOB
* value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers
* may support this operation.
*
* @param pos the position in the BLOB object at which to start writing; the first position is 1
* @param bytes the array of bytes to be written to the BLOB value that this Blob object
* represents
* @return the number of bytes written
* @see #getBytes
* @since 1.4
*/
public int setBytes(final long pos, final byte[] bytes) throws SQLException {
final int arrayPos = (int) pos - 1;
final int bytesWritten;
if (blobContent == null) {
this.blobContent = new byte[arrayPos + bytes.length];
bytesWritten = blobContent.length;
this.actualSize = bytesWritten;
} else if (blobContent.length > arrayPos + bytes.length) {
bytesWritten = bytes.length;
} else {
blobContent = Utils.copyWithLength(blobContent, arrayPos + bytes.length);
actualSize = blobContent.length;
bytesWritten = bytes.length;
}
System.arraycopy(bytes, 0, this.blobContent, arrayPos, bytes.length);
return bytesWritten;
}
/**
* Writes all or part of the given byte array to the BLOB value that this
* Blob object represents and returns the number of bytes written. Writing starts at position
* pos in the BLOB value; len bytes from the given byte array are written.
* The array of bytes will overwrite the existing bytes in the Blob object starting at the position
* pos. If the end of the Blob value is reached while writing the array of bytes, then
* the length of the Blob value will be increased to accomodate the extra bytes.
*
* Note: If the value specified for pos is greater then the length+1 of the BLOB
* value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers
* may support this operation.
*
* @param pos the position in the BLOB object at which to start writing; the first position is 1
* @param bytes the array of bytes to be written to this BLOB object
* @param offset the offset into the array bytes at which to start reading the bytes to be set
* @param len the number of bytes to be written to the BLOB value from the array of bytes
* bytes
* @return the number of bytes written
* @throws java.sql.SQLException if there is an error accessing the BLOB value or if pos is less than
* 1
* @see #getBytes
*/
public int setBytes(final long pos,
final byte[] bytes,
final int offset,
final int len) throws SQLException {
int bytesWritten = 0;
if (blobContent == null) {
this.blobContent = new byte[(int) (pos + bytes.length) - (len - offset)];
for (int i = (int) pos + offset; i < len; i++) {
this.blobContent[((int) (pos + i))] = bytes[i];
bytesWritten++;
}
} else if (this.blobContent.length < (pos + bytes.length) - (len - offset)) {
for (int i = (int) pos + offset; i < len; i++) {
this.blobContent[((int) (pos + i))] = bytes[i];
bytesWritten++;
}
}
this.actualSize += bytesWritten;
return bytesWritten;
}
/**
* Retrieves a stream that can be used to write to the BLOB value that this Blob object
* represents. The stream begins at position pos. The bytes written to the stream will overwrite the
* existing bytes in the Blob object starting at the position pos. If the end of the
* Blob value is reached while writing to the stream, then the length of the Blob value
* will be increased to accomodate the extra bytes.
*
* Note: If the value specified for pos is greater then the length+1 of the BLOB
* value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers
* may support this operation.
*
* @param pos the position in the BLOB value at which to start writing; the first position is 1
* @return a java.io.OutputStream object to which data can be written
* @throws java.sql.SQLException if there is an error accessing the BLOB value or if pos is less than
* 1
* @see #getBinaryStream
* @since 1.4
*/
public OutputStream setBinaryStream(final long pos) throws SQLException {
if (pos < 1) {
throw SQLExceptionMapper.getSQLException("Invalid position in blob");
}
return new DrizzleBlob(Utils.copyRange(blobContent,
(int) pos - 1, blobContent.length + 1));
}
/**
* Truncates the BLOB value that this Blob object represents to be len bytes
* in length.
*
* Note: If the value specified for pos is greater then the length+1 of the BLOB
* value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers
* may support this operation.
*
* @param len the length, in bytes, to which the BLOB value that this Blob object
* represents should be truncated
* @throws java.sql.SQLException if there is an error accessing the BLOB value or if len is less than
* 0
*/
public void truncate(final long len) throws SQLException {
this.blobContent = Utils.copyWithLength(this.blobContent, (int) len);
this.actualSize = (int) len;
}
/**
* This method frees the Blob object and releases the resources that it holds. The object is invalid
* once the free method is called.
*
* After free has been called, any attempt to invoke a method other than free will result
* in a SQLException being thrown. If free is called multiple times, the subsequent calls
* to free are treated as a no-op.
*
*/
public void free() {
this.blobContent = null;
this.actualSize = 0;
}
/**
* Returns an InputStream object that contains a partial Blob value, starting with the
* byte specified by pos, which is length bytes in length.
*
* @param pos the offset to the first byte of the partial value to be retrieved. The first byte in the
* Blob is at position 1
* @param length the length in bytes of the partial value to be retrieved
* @return InputStream through which the partial Blob value can be read.
* @throws java.sql.SQLException if pos is less than 1 or if pos is greater than the number of bytes in the
* Blob or if pos + length is greater than the number of bytes in the
* Blob
*/
public InputStream getBinaryStream(final long pos, final long length) throws SQLException {
if (pos < 1 || pos > actualSize || pos + length > actualSize) {
throw SQLExceptionMapper.getSQLException("Out of range");
}
return new ByteArrayInputStream(Utils.copyRange(blobContent,
(int) pos,
(int) length));
}
}