| /* |
| * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package javax.sql.rowset.serial; |
| |
| import java.sql.*; |
| import java.io.*; |
| import java.lang.reflect.*; |
| import java.util.Arrays; |
| |
| |
| /** |
| * A serialized mapping in the Java programming language of an SQL |
| * <code>BLOB</code> value. |
| * <P> |
| * The <code>SerialBlob</code> class provides a constructor for creating |
| * an instance from a <code>Blob</code> object. Note that the |
| * <code>Blob</code> |
| * object should have brought the SQL <code>BLOB</code> value's data over |
| * to the client before a <code>SerialBlob</code> object |
| * is constructed from it. The data of an SQL <code>BLOB</code> value can |
| * be materialized on the client as an array of bytes (using the method |
| * <code>Blob.getBytes</code>) or as a stream of uninterpreted bytes |
| * (using the method <code>Blob.getBinaryStream</code>). |
| * <P> |
| * <code>SerialBlob</code> methods make it possible to make a copy of a |
| * <code>SerialBlob</code> object as an array of bytes or as a stream. |
| * They also make it possible to locate a given pattern of bytes or a |
| * <code>Blob</code> object within a <code>SerialBlob</code> object |
| * and to update or truncate a <code>Blob</code> object. |
| * |
| * <h3> Thread safety </h3> |
| * |
| * <p> A SerialBlob is not safe for use by multiple concurrent threads. If a |
| * SerialBlob is to be used by more than one thread then access to the SerialBlob |
| * should be controlled by appropriate synchronization. |
| * |
| * @author Jonathan Bruce |
| * @since 1.5 |
| */ |
| public class SerialBlob implements Blob, Serializable, Cloneable { |
| |
| /** |
| * A serialized array of uninterpreted bytes representing the |
| * value of this <code>SerialBlob</code> object. |
| * @serial |
| */ |
| private byte buf[]; |
| |
| /** |
| * The internal representation of the <code>Blob</code> object on which this |
| * <code>SerialBlob</code> object is based. |
| */ |
| private Blob blob; |
| |
| /** |
| * The number of bytes in this <code>SerialBlob</code> object's |
| * array of bytes. |
| * @serial |
| */ |
| private long len; |
| |
| /** |
| * The original number of bytes in this <code>SerialBlob</code> object's |
| * array of bytes when it was first established. |
| * @serial |
| */ |
| private long origLen; |
| |
| /** |
| * Constructs a <code>SerialBlob</code> object that is a serialized version of |
| * the given <code>byte</code> array. |
| * <p> |
| * The new <code>SerialBlob</code> object is initialized with the data from the |
| * <code>byte</code> array, thus allowing disconnected <code>RowSet</code> |
| * objects to establish serialized <code>Blob</code> objects without |
| * touching the data source. |
| * |
| * @param b the <code>byte</code> array containing the data for the |
| * <code>Blob</code> object to be serialized |
| * @throws SerialException if an error occurs during serialization |
| * @throws SQLException if a SQL errors occurs |
| */ |
| public SerialBlob(byte[] b) throws SerialException, SQLException { |
| |
| len = b.length; |
| buf = new byte[(int)len]; |
| for(int i = 0; i < len; i++) { |
| buf[i] = b[i]; |
| } |
| origLen = len; |
| } |
| |
| |
| /** |
| * Constructs a <code>SerialBlob</code> object that is a serialized |
| * version of the given <code>Blob</code> object. |
| * <P> |
| * The new <code>SerialBlob</code> object is initialized with the |
| * data from the <code>Blob</code> object; therefore, the |
| * <code>Blob</code> object should have previously brought the |
| * SQL <code>BLOB</code> value's data over to the client from |
| * the database. Otherwise, the new <code>SerialBlob</code> object |
| * will contain no data. |
| * |
| * @param blob the <code>Blob</code> object from which this |
| * <code>SerialBlob</code> object is to be constructed; |
| * cannot be null. |
| * @throws SerialException if an error occurs during serialization |
| * @throws SQLException if the <code>Blob</code> passed to this |
| * to this constructor is a <code>null</code>. |
| * @see java.sql.Blob |
| */ |
| public SerialBlob (Blob blob) throws SerialException, SQLException { |
| |
| if (blob == null) { |
| throw new SQLException("Cannot instantiate a SerialBlob " + |
| "object with a null Blob object"); |
| } |
| |
| len = blob.length(); |
| buf = blob.getBytes(1, (int)len ); |
| this.blob = blob; |
| |
| //if ( len < 10240000) |
| // len = 10240000; |
| origLen = len; |
| } |
| |
| /** |
| * Copies the specified number of bytes, starting at the given |
| * position, from this <code>SerialBlob</code> object to |
| * another array of bytes. |
| * <P> |
| * Note that if the given number of bytes to be copied is larger than |
| * the length of this <code>SerialBlob</code> object's array of |
| * bytes, the given number will be shortened to the array's length. |
| * |
| * @param pos the ordinal position of the first byte in this |
| * <code>SerialBlob</code> object to be copied; |
| * numbering starts at <code>1</code>; must not be less |
| * than <code>1</code> and must be less than or equal |
| * to the length of this <code>SerialBlob</code> object |
| * @param length the number of bytes to be copied |
| * @return an array of bytes that is a copy of a region of this |
| * <code>SerialBlob</code> object, starting at the given |
| * position and containing the given number of consecutive bytes |
| * @throws SerialException if the given starting position is out of bounds; |
| * if {@code free} had previously been called on this object |
| */ |
| public byte[] getBytes(long pos, int length) throws SerialException { |
| isValid(); |
| if (length > len) { |
| length = (int)len; |
| } |
| |
| if (pos < 1 || len - pos < 0 ) { |
| throw new SerialException("Invalid arguments: position cannot be " |
| + "less than 1 or greater than the length of the SerialBlob"); |
| } |
| |
| pos--; // correct pos to array index |
| |
| byte[] b = new byte[length]; |
| |
| for (int i = 0; i < length; i++) { |
| b[i] = this.buf[(int)pos]; |
| pos++; |
| } |
| return b; |
| } |
| |
| /** |
| * Retrieves the number of bytes in this <code>SerialBlob</code> |
| * object's array of bytes. |
| * |
| * @return a <code>long</code> indicating the length in bytes of this |
| * <code>SerialBlob</code> object's array of bytes |
| * @throws SerialException if an error occurs; |
| * if {@code free} had previously been called on this object |
| */ |
| public long length() throws SerialException { |
| isValid(); |
| return len; |
| } |
| |
| /** |
| * Returns this <code>SerialBlob</code> object as an input stream. |
| * Unlike the related method, <code>setBinaryStream</code>, |
| * a stream is produced regardless of whether the <code>SerialBlob</code> |
| * was created with a <code>Blob</code> object or a <code>byte</code> array. |
| * |
| * @return a <code>java.io.InputStream</code> object that contains |
| * this <code>SerialBlob</code> object's array of bytes |
| * @throws SerialException if an error occurs; |
| * if {@code free} had previously been called on this object |
| * @see #setBinaryStream |
| */ |
| public java.io.InputStream getBinaryStream() throws SerialException { |
| isValid(); |
| InputStream stream = new ByteArrayInputStream(buf); |
| return stream; |
| } |
| |
| /** |
| * Returns the position in this <code>SerialBlob</code> object where |
| * the given pattern of bytes begins, starting the search at the |
| * specified position. |
| * |
| * @param pattern the pattern of bytes for which to search |
| * @param start the position of the byte in this |
| * <code>SerialBlob</code> object from which to begin |
| * the search; the first position is <code>1</code>; |
| * must not be less than <code>1</code> nor greater than |
| * the length of this <code>SerialBlob</code> object |
| * @return the position in this <code>SerialBlob</code> object |
| * where the given pattern begins, starting at the specified |
| * position; <code>-1</code> if the pattern is not found |
| * or the given starting position is out of bounds; position |
| * numbering for the return value starts at <code>1</code> |
| * @throws SerialException if an error occurs when serializing the blob; |
| * if {@code free} had previously been called on this object |
| * @throws SQLException if there is an error accessing the <code>BLOB</code> |
| * value from the database |
| */ |
| public long position(byte[] pattern, long start) |
| throws SerialException, SQLException { |
| isValid(); |
| if (start < 1 || start > len) { |
| return -1; |
| } |
| |
| int pos = (int)start-1; // internally Blobs are stored as arrays. |
| int i = 0; |
| long patlen = pattern.length; |
| |
| while (pos < len) { |
| if (pattern[i] == buf[pos]) { |
| if (i + 1 == patlen) { |
| return (pos + 1) - (patlen - 1); |
| } |
| i++; pos++; // increment pos, and i |
| } else if (pattern[i] != buf[pos]) { |
| pos++; // increment pos only |
| } |
| } |
| return -1; // not found |
| } |
| |
| /** |
| * Returns the position in this <code>SerialBlob</code> object where |
| * the given <code>Blob</code> object begins, starting the search at the |
| * specified position. |
| * |
| * @param pattern the <code>Blob</code> object for which to search; |
| * @param start the position of the byte in this |
| * <code>SerialBlob</code> object from which to begin |
| * the search; the first position is <code>1</code>; |
| * must not be less than <code>1</code> nor greater than |
| * the length of this <code>SerialBlob</code> object |
| * @return the position in this <code>SerialBlob</code> object |
| * where the given <code>Blob</code> object begins, starting |
| * at the specified position; <code>-1</code> if the pattern is |
| * not found or the given starting position is out of bounds; |
| * position numbering for the return value starts at <code>1</code> |
| * @throws SerialException if an error occurs when serializing the blob; |
| * if {@code free} had previously been called on this object |
| * @throws SQLException if there is an error accessing the <code>BLOB</code> |
| * value from the database |
| */ |
| public long position(Blob pattern, long start) |
| throws SerialException, SQLException { |
| isValid(); |
| return position(pattern.getBytes(1, (int)(pattern.length())), start); |
| } |
| |
| /** |
| * Writes the given array of bytes to the <code>BLOB</code> value that |
| * this <code>Blob</code> object represents, starting at position |
| * <code>pos</code>, and returns the number of bytes written. |
| * |
| * @param pos the position in the SQL <code>BLOB</code> value at which |
| * to start writing. The first position is <code>1</code>; |
| * must not be less than <code>1</code> nor greater than |
| * the length of this <code>SerialBlob</code> object. |
| * @param bytes the array of bytes to be written to the <code>BLOB</code> |
| * value that this <code>Blob</code> object represents |
| * @return the number of bytes written |
| * @throws SerialException if there is an error accessing the |
| * <code>BLOB</code> value; or if an invalid position is set; if an |
| * invalid offset value is set; |
| * if {@code free} had previously been called on this object |
| * @throws SQLException if there is an error accessing the <code>BLOB</code> |
| * value from the database |
| * @see #getBytes |
| */ |
| public int setBytes(long pos, byte[] bytes) |
| throws SerialException, SQLException { |
| return (setBytes(pos, bytes, 0, bytes.length)); |
| } |
| |
| /** |
| * Writes all or part of the given <code>byte</code> array to the |
| * <code>BLOB</code> value that this <code>Blob</code> object represents |
| * and returns the number of bytes written. |
| * Writing starts at position <code>pos</code> in the <code>BLOB</code> |
| * value; <i>len</i> bytes from the given byte array are written. |
| * |
| * @param pos the position in the <code>BLOB</code> object at which |
| * to start writing. The first position is <code>1</code>; |
| * must not be less than <code>1</code> nor greater than |
| * the length of this <code>SerialBlob</code> object. |
| * @param bytes the array of bytes to be written to the <code>BLOB</code> |
| * value |
| * @param offset the offset in the <code>byte</code> array at which |
| * to start reading the bytes. The first offset position is |
| * <code>0</code>; must not be less than <code>0</code> nor greater |
| * than the length of the <code>byte</code> array |
| * @param length the number of bytes to be written to the |
| * <code>BLOB</code> value from the array of bytes <i>bytes</i>. |
| * |
| * @return the number of bytes written |
| * @throws SerialException if there is an error accessing the |
| * <code>BLOB</code> value; if an invalid position is set; if an |
| * invalid offset value is set; if number of bytes to be written |
| * is greater than the <code>SerialBlob</code> length; or the combined |
| * values of the length and offset is greater than the Blob buffer; |
| * if {@code free} had previously been called on this object |
| * @throws SQLException if there is an error accessing the <code>BLOB</code> |
| * value from the database. |
| * @see #getBytes |
| */ |
| public int setBytes(long pos, byte[] bytes, int offset, int length) |
| throws SerialException, SQLException { |
| |
| isValid(); |
| if (offset < 0 || offset > bytes.length) { |
| throw new SerialException("Invalid offset in byte array set"); |
| } |
| |
| if (pos < 1 || pos > this.length()) { |
| throw new SerialException("Invalid position in BLOB object set"); |
| } |
| |
| if ((long)(length) > origLen) { |
| throw new SerialException("Buffer is not sufficient to hold the value"); |
| } |
| |
| if ((length + offset) > bytes.length) { |
| throw new SerialException("Invalid OffSet. Cannot have combined offset " + |
| "and length that is greater that the Blob buffer"); |
| } |
| |
| int i = 0; |
| pos--; // correct to array indexing |
| while ( i < length || (offset + i +1) < (bytes.length-offset) ) { |
| this.buf[(int)pos + i] = bytes[offset + i ]; |
| i++; |
| } |
| return i; |
| } |
| |
| /** |
| * Retrieves a stream that can be used to write to the <code>BLOB</code> |
| * value that this <code>Blob</code> object represents. The stream begins |
| * at position <code>pos</code>. This method forwards the |
| * <code>setBinaryStream()</code> call to the underlying <code>Blob</code> in |
| * the event that this <code>SerialBlob</code> object is instantiated with a |
| * <code>Blob</code>. If this <code>SerialBlob</code> is instantiated with |
| * a <code>byte</code> array, a <code>SerialException</code> is thrown. |
| * |
| * @param pos the position in the <code>BLOB</code> value at which |
| * to start writing |
| * @return a <code>java.io.OutputStream</code> object to which data can |
| * be written |
| * @throws SQLException if there is an error accessing the |
| * <code>BLOB</code> value |
| * @throws SerialException if the SerialBlob in not instantiated with a |
| * <code>Blob</code> object that supports <code>setBinaryStream()</code>; |
| * if {@code free} had previously been called on this object |
| * @see #getBinaryStream |
| */ |
| public java.io.OutputStream setBinaryStream(long pos) |
| throws SerialException, SQLException { |
| isValid(); |
| if (this.blob != null) { |
| return this.blob.setBinaryStream(pos); |
| } else { |
| throw new SerialException("Unsupported operation. SerialBlob cannot " + |
| "return a writable binary stream, unless instantiated with a Blob object " + |
| "that provides a setBinaryStream() implementation"); |
| } |
| } |
| |
| /** |
| * Truncates the <code>BLOB</code> value that this <code>Blob</code> |
| * object represents to be <code>len</code> bytes in length. |
| * |
| * @param length the length, in bytes, to which the <code>BLOB</code> |
| * value that this <code>Blob</code> object represents should be |
| * truncated |
| * @throws SerialException if there is an error accessing the Blob value; |
| * or the length to truncate is greater that the SerialBlob length; |
| * if {@code free} had previously been called on this object |
| */ |
| public void truncate(long length) throws SerialException { |
| |
| isValid(); |
| if (length > len) { |
| throw new SerialException |
| ("Length more than what can be truncated"); |
| } else if((int)length == 0) { |
| buf = new byte[0]; |
| len = length; |
| } else { |
| len = length; |
| buf = this.getBytes(1, (int)len); |
| } |
| } |
| |
| |
| /** |
| * Returns an |
| * <code>InputStream</code> object that contains a partial |
| * {@code 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 {@code Blob} is at position 1 |
| * @param length the length in bytes of the partial value to be retrieved |
| * @return |
| * <code>InputStream</code> through which the partial {@code Blob} value can |
| * be read. |
| * @throws SQLException if pos is less than 1 or if pos is greater than the |
| * number of bytes in the {@code Blob} or if pos + length is greater than |
| * the number of bytes in the {@code Blob} |
| * @throws SerialException if the {@code free} method had been previously |
| * called on this object |
| * |
| * @since 1.6 |
| */ |
| public InputStream getBinaryStream(long pos, long length) throws SQLException { |
| isValid(); |
| if (pos < 1 || pos > this.length()) { |
| throw new SerialException("Invalid position in BLOB object set"); |
| } |
| if (length < 1 || length > len - pos + 1) { |
| throw new SerialException("length is < 1 or pos + length >" |
| + "total number of bytes"); |
| } |
| return new ByteArrayInputStream(buf, (int) pos - 1, (int) length); |
| } |
| |
| |
| /** |
| * This method frees the {@code SeriableBlob} object and releases the |
| * resources that it holds. The object is invalid once the {@code free} |
| * method is called. <p> If {@code free} is called multiple times, the |
| * subsequent calls to {@code free} are treated as a no-op. </P> |
| * |
| * @throws SQLException if an error occurs releasing the Blob's resources |
| * @since 1.6 |
| */ |
| public void free() throws SQLException { |
| if (buf != null) { |
| buf = null; |
| if (blob != null) { |
| blob.free(); |
| } |
| blob = null; |
| } |
| } |
| |
| /** |
| * Compares this SerialBlob to the specified object. The result is {@code |
| * true} if and only if the argument is not {@code null} and is a {@code |
| * SerialBlob} object that represents the same sequence of bytes as this |
| * object. |
| * |
| * @param obj The object to compare this {@code SerialBlob} against |
| * |
| * @return {@code true} if the given object represents a {@code SerialBlob} |
| * equivalent to this SerialBlob, {@code false} otherwise |
| * |
| */ |
| public boolean equals(Object obj) { |
| if (this == obj) { |
| return true; |
| } |
| if (obj instanceof SerialBlob) { |
| SerialBlob sb = (SerialBlob)obj; |
| if (this.len == sb.len) { |
| return Arrays.equals(buf, sb.buf); |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Returns a hash code for this {@code SerialBlob}. |
| * @return a hash code value for this object. |
| */ |
| public int hashCode() { |
| return ((31 + Arrays.hashCode(buf)) * 31 + (int)len) * 31 + (int)origLen; |
| } |
| |
| /** |
| * Returns a clone of this {@code SerialBlob}. The copy will contain a |
| * reference to a clone of the internal byte array, not a reference |
| * to the original internal byte array of this {@code SerialBlob} object. |
| * The underlying {@code Blob} object will be set to null. |
| * |
| * @return a clone of this SerialBlob |
| */ |
| public Object clone() { |
| try { |
| SerialBlob sb = (SerialBlob) super.clone(); |
| sb.buf = (buf != null) ? Arrays.copyOf(buf, (int)len) : null; |
| sb.blob = null; |
| return sb; |
| } catch (CloneNotSupportedException ex) { |
| // this shouldn't happen, since we are Cloneable |
| throw new InternalError(); |
| } |
| |
| } |
| |
| /** |
| * readObject is called to restore the state of the SerialBlob from |
| * a stream. |
| */ |
| private void readObject(ObjectInputStream s) |
| throws IOException, ClassNotFoundException { |
| |
| ObjectInputStream.GetField fields = s.readFields(); |
| byte[] tmp = (byte[])fields.get("buf", null); |
| if (tmp == null) |
| throw new InvalidObjectException("buf is null and should not be!"); |
| buf = tmp.clone(); |
| len = fields.get("len", 0L); |
| if (buf.length != len) |
| throw new InvalidObjectException("buf is not the expected size"); |
| origLen = fields.get("origLen", 0L); |
| blob = (Blob) fields.get("blob", null); |
| } |
| |
| /** |
| * writeObject is called to save the state of the SerialBlob |
| * to a stream. |
| */ |
| private void writeObject(ObjectOutputStream s) |
| throws IOException, ClassNotFoundException { |
| |
| ObjectOutputStream.PutField fields = s.putFields(); |
| fields.put("buf", buf); |
| fields.put("len", len); |
| fields.put("origLen", origLen); |
| // Note: this check to see if it is an instance of Serializable |
| // is for backwards compatibiity |
| fields.put("blob", blob instanceof Serializable ? blob : null); |
| s.writeFields(); |
| } |
| |
| /** |
| * Check to see if this object had previously had its {@code free} method |
| * called |
| * |
| * @throws SerialException |
| */ |
| private void isValid() throws SerialException { |
| if (buf == null) { |
| throw new SerialException("Error: You cannot call a method on a " |
| + "SerialBlob instance once free() has been called."); |
| } |
| } |
| |
| /** |
| * The identifier that assists in the serialization of this |
| * {@code SerialBlob} object. |
| */ |
| static final long serialVersionUID = -8144641928112860441L; |
| } |
