- /*
- * @(#)SerialClob.java 1.11 04/08/10
- *
- * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
-
- package javax.sql.rowset.serial;
-
- import java.sql.*;
- import java.io.*;
-
- /**
- * A serialized mapping in the Java programming language of an SQL
- * <code>CLOB</code> value.
- * <P>
- * The <code>SerialClob</code> class provides a constructor for creating
- * an instance from a <code>Clob</code> object. Note that the <code>Clob</code>
- * object should have brought the SQL <code>CLOB</code> value's data over
- * to the client before a <code>SerialClob</code> object
- * is constructed from it. The data of an SQL <code>CLOB</code> value can
- * be materialized on the client as a stream of Unicode characters.
- * <P>
- * <code>SerialClob</code> methods make it possible to get a substring
- * from a <code>SerialClob</code> object or to locate the start of
- * a pattern of characters.
- *
- * @author Jonathan Bruce
- */
- public class SerialClob implements Clob, Serializable, Cloneable {
-
- /**
- * A serialized array of characters containing the data of the SQL
- * <code>CLOB</code> value that this <code>SerialClob</code> object
- * represents.
- *
- * @serial
- */
- private char buf[];
-
- /**
- * Internal Clob representation if SerialClob is intialized with a
- * Clob
- */
- private Clob clob;
-
- /**
- * The length in characters of this <code>SerialClob</code> object's
- * internal array of characters.
- *
- * @serial
- */
- private long len;
-
- /**
- * The original length in characters of tgus <code>SerialClob</code>
- * objects internal array of characters.
- *
- * @serial
- */
- private long origLen;
-
- /**
- * Constructs a <code>SerialClob</code> object that is a serialized version of
- * the given <code>char</code> array.
- * <p>
- * The new <code>SerialClob</code> object is initialized with the data from the
- * <code>char</code> array, thus allowing disconnected <code>RowSet</code>
- * objects to establish a serialized <code>Clob</code> object without touching
- * the data source.
- *
- * @param ch the char array representing the <code>Clob</code> object to be
- * serialized
- * @throws SerialException if an error occurs during serialization
- * @throws SQLException if a SQL error occurs
- */
- public SerialClob(char ch[]) throws SerialException, SQLException {
-
- // %%% JMB. Agreed. Add code here to throw a SQLException if no
- // support is available for locatorsUpdateCopy=false
- // Serializing locators is not supported.
-
- len = ch.length;
- buf = new char[(int)len];
- for (int i = 0; i < len ; i++){
- buf[i] = ch[i];
- }
- origLen = len;
- }
-
- /**
- * Constructs a <code>SerialClob</code> object that is a serialized
- * version of the given <code>Clob</code> object.
- * <P>
- * The new <code>SerialClob</code> object is initialized with the
- * data from the <code>Clob</code> object; therefore, the
- * <code>Clob</code> object should have previously brought the
- * SQL <code>CLOB</code> value's data over to the client from
- * the database. Otherwise, the new <code>SerialClob</code> object
- * object will contain no data.
- * <p>
- * Note: The <code>Clob</code> object supplied to this constructor cannot
- * return <code>null</code> for the <code>Clob.getCharacterStream()</code>
- * and <code>Clob.getAsciiStream</code> methods. This <code>SerialClob</code>
- * constructor cannot serialize a <code>Clob</code> object in this instance
- * and will throw an <code>SQLException</code> object.
- *
- * @param clob the <code>Clob</code> object from which this
- * <code>SerialClob</code> object is to be constructed; cannot be null
- * @throws SerialException if an error occurs during serialization
- * @throws SQLException if a SQL error occurs in capturing the CLOB;
- * if the <code>Clob</code> object is a null; or if at least one of the
- * <code>Clob.getCharacterStream()</code> and <code>Clob.getAsciiStream()</code>
- * methods on the <code>Clob</code> return a null
- * @see java.sql.Clob
- */
- public SerialClob(Clob clob) throws SerialException, SQLException {
-
- if (clob == null) {
- throw new SQLException("Cannot instantiate a SerialClob " +
- "object with a null Clob object");
- }
- len = clob.length();
- this.clob = clob;
- buf = new char[(int)len];
- int read = 0;
- int offset = 0;
-
- BufferedReader reader;
-
- if (clob.getCharacterStream() == null || clob.getAsciiStream() == null) {
- throw new SQLException("Invalid Clob object. Calls to getCharacterStream " +
- "or getAsciiStream return null which cannot be serialized.");
- }
-
- try {
- reader = new BufferedReader(clob.getCharacterStream());
-
- do {
- read = reader.read(buf, offset, (int)(len - offset));
- offset += read;
- } while (read > 0);
-
- } catch (java.io.IOException ex) {
- throw new SerialException("SerialClob: " + ex.getMessage());
- }
-
- origLen = len;
- }
-
- /**
- * Retrieves the number of characters in this <code>SerialClob</code>
- * object's array of characters.
- *
- * @return a <code>long</code> indicating the length in characters of this
- * <code>SerialClob</code> object's array of character
- * @throws SerialException if an error occurs
- */
- public long length() throws SerialException {
- return len;
- }
-
- /**
- * Returns this <code>SerialClob</code> object's data as a stream
- * of Unicode characters. Unlike the related method, <code>getAsciiStream</code>,
- * a stream is produced regardless of whether the <code>SerialClob</code> object
- * was created with a <code>Clob</code> object or a <code>char</code> array.
- *
- * @return a <code>java.io.Reader</code> object containing this
- * <code>SerialClob</code> object's data
- * @throws SerialException if an error occurs
- */
- public java.io.Reader getCharacterStream() throws SerialException {
- return (java.io.Reader) new CharArrayReader(buf);
- }
-
- /**
- * Retrieves the <code>CLOB</code> value designated by this <code>SerialClob</code>
- * object as an ascii stream. This method forwards the <code>getAsciiStream</code>
- * call to the underlying <code>Clob</code> object in the event that this
- * <code>SerialClob</code> object is instantiated with a <code>Clob</code>
- * object. If this <code>SerialClob</code> object is instantiated with
- * a <code>char</code> array, a <code>SerialException</code> object is thrown.
- *
- * @return a <code>java.io.InputStream</code> object containing
- * this <code>SerialClob</code> object's data
- * @throws SerialException if this <code>SerialClob<code> object was not instantiated
- * with a <code>Clob</code> object
- * @throws SQLException if there is an error accessing the
- * <code>CLOB</code> value represented by the <code>Clob</code> object that was
- * used to create this <code>SerialClob</code> object
- */
- public java.io.InputStream getAsciiStream() throws SerialException, SQLException {
- if (this.clob != null) {
- return this.clob.getAsciiStream();
- } else {
- throw new SerialException("Unsupported operation. SerialClob cannot " +
- "return a the CLOB value as an ascii stream, unless instantiated " +
- "with a fully implemented Clob object.");
- }
- }
-
- /**
- * Returns a copy of the substring contained in this
- * <code>SerialClob</code> object, starting at the given position
- * and continuing for the specified number or characters.
- *
- * @param pos the position of the first character in the substring
- * to be copied; the first character of the
- * <code>SerialClob</code> object is at position
- * <code>1</code> must not be less than <code>1</code>,
- * and the sum of the starting position and the length
- * of the substring must be less than the length of this
- * <code>SerialClob</code> object
- * @param length the number of characters in the substring to be
- * returned; must not be greater than the length of
- * this <code>SerialClob</code> object, and the
- * sum of the starting position and the length
- * of the substring must be less than the length of this
- * <code>SerialClob</code> object
- * @return a <code>String</code> object containing a substring of
- * this <code>SerialClob</code> object beginning at the
- * given position and containing the specified number of
- * consecutive characters
- * @throws SerialException if either of the arguments is out of bounds
- */
- public String getSubString(long pos, int length) throws SerialException {
-
- if (pos < 1 || pos > this.length()) {
- throw new SerialException("Invalid position in BLOB object set");
- }
-
- if ((pos-1) + length > this.length()) {
- throw new SerialException("Invalid position and substring length");
- }
-
- try {
- return new String(buf, (int)pos - 1, length);
-
- } catch (StringIndexOutOfBoundsException e) {
- throw new SerialException("StringIndexOutOfBoundsException: " +
- e.getMessage());
- }
-
- }
-
- /**
- * Returns the position in this <code>SerialClob</code> object
- * where the given <code>String</code> object begins, starting
- * the search at the specified position. This method returns
- * <code>-1</code> if the pattern is not found.
- *
- * @param searchStr the <code>String</code> object for which to
- * search
- * @param start the position in this <code>SerialClob</code> object
- * at which to start 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>SerialClob</code> object
- * @return the position at which the given <code>String</code> object
- * begins, starting the search at the specified position;
- * <code>-1</code> if the given <code>String</code> object is
- * not found or the starting position is out of bounds; position
- * numbering for the return value starts at <code>1</code>
- * @throws SerialException if an error occurs locating the String signature
- * @throws SQLException if there is an error accessing the Blob value
- * from the database.
- */
- public long position(String searchStr, long start)
- throws SerialException, SQLException {
-
- if (start < 1 || start > len) {
- return -1;
- }
-
- char pattern[] = searchStr.toCharArray();
-
- int pos = (int)start-1;
- 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>SerialClob</code> object
- * where the given <code>Clob</code> signature begins, starting
- * the search at the specified position. This method returns
- * <code>-1</code> if the pattern is not found.
- *
- * @param searchStr the <code>Clob</code> object for which to search
- * @param start the position in this <code>SerialClob</code> object
- * at 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>SerialClob</code> object
- * @return the position at which the given <code>Clob</code>
- * object begins in this <code>SerialClob</code> object,
- * at or after the specified starting position
- * @throws SerialException if an error occurs locating the Clob signature
- * @throws SQLException if there is an error accessing the Blob value
- * from the database
- */
- public long position(Clob searchStr, long start)
- throws SerialException, SQLException {
-
- char cPattern[] = null;
- try {
- java.io.Reader r = searchStr.getCharacterStream();
- cPattern = new char[(int)searchStr.length()];
- r.read(cPattern);
- } catch (IOException e) {
- throw new SerialException("Error streaming Clob search data");
- }
- return position(new String(cPattern), start);
- }
-
- /**
- * Writes the given Java <code>String</code> to the <code>CLOB</code>
- * value that this <code>SerialClob</code> object represents, at the position
- * <code>pos</code>.
- *
- * @param pos the position at which to start writing to the <code>CLOB</code>
- * value that this <code>SerialClob</code> object represents; the first
- * position is <code>1</code> must not be less than <code>1</code> nor
- * greater than the length of this <code>SerialClob</code> object
- * @param str the string to be written to the <code>CLOB</code>
- * value that this <code>SerialClob</code> object represents
- * @return the number of characters written
- * @throws SerialException if there is an error accessing the
- * <code>CLOB</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>SerialClob</code> length; or the combined
- * values of the length and offset is greater than the Clob buffer
- */
- public int setString(long pos, String str) throws SerialException {
- return (setString(pos, str, 0, str.length()));
- }
-
- /**
- * Writes <code>len</code> characters of <code>str</code>, starting
- * at character <code>offset</code>, to the <code>CLOB</code> value
- * that this <code>Clob</code> represents.
- *
- * @param pos the position at which to start writing to the <code>CLOB</code>
- * value that this <code>SerialClob</code> object represents; the first
- * position is <code>1</code> must not be less than <code>1</code> nor
- * greater than the length of this <code>SerialClob</code> object
- * @param str the string to be written to the <code>CLOB</code>
- * value that this <code>Clob</code> object represents
- * @param offset the offset into <code>str</code> to start reading
- * the characters to be written
- * @param length the number of characters to be written
- * @return the number of characters written
- * @throws SerialException if there is an error accessing the
- * <code>CLOB</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>SerialClob</code> length; or the combined
- * values of the length and offset is greater than the Clob buffer
- */
- public int setString(long pos, String str, int offset, int length)
- throws SerialException {
- String temp = str.substring(offset);
- char cPattern[] = temp.toCharArray();
-
- if (offset < 0 || offset > str.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) > str.length()) {
- // need check to ensure 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--; //values in the array are at position one less
- while ( i < length || (offset + i +1) < (str.length() - offset ) ) {
- this.buf[(int)pos + i ] = cPattern[offset + i ];
- i++;
- }
- return i;
- }
-
- /**
- * Retrieves a stream to be used to write Ascii characters to the
- * <code>CLOB</code> value that this <code>SerialClob</code> object represents,
- * starting at position <code>pos</code>. This method forwards the
- * <code>setAsciiStream()</code> call to the underlying <code>Clob</code> object in
- * the event that this <code>SerialClob</code> object is instantiated with a
- * <code>Clob</code> object. If this <code>SerialClob</code> object is instantiated
- * with a <code>char</code> array, a <code>SerialException</code> object is thrown.
- *
- * @param pos the position at which to start writing to the
- * <code>CLOB</code> object
- * @return the stream to which ASCII encoded characters can be written
- * @throws SerialException if SerialClob is not instantiated with a
- * Clob object that supports <code>setAsciiStream</code>
- * @throws SQLException if there is an error accessing the
- * <code>CLOB</code> value
- * @see #getAsciiStream
- */
- public java.io.OutputStream setAsciiStream(long pos)
- throws SerialException, SQLException {
- if (this.clob.setAsciiStream(pos) != null) {
- return this.clob.setAsciiStream(pos);
- } else {
- throw new SerialException("Unsupported operation. SerialClob cannot " +
- "return a writable ascii stream\n unless instantiated with a Clob object " +
- "that has a setAsciiStream() implementation");
- }
- }
-
- /**
- * Retrieves a stream to be used to write a stream of Unicode characters
- * to the <code>CLOB</code> value that this <code>SerialClob</code> object
- * represents, at position <code>pos</code>. This method forwards the
- * <code>setCharacterStream()</code> call to the underlying <code>Clob</code>
- * object in the event that this <code>SerialClob</code> object is instantiated with a
- * <code>Clob</code> object. If this <code>SerialClob</code> object is instantiated with
- * a <code>char</code> array, a <code>SerialException</code> is thrown.
- *
- * @param pos the position at which to start writing to the
- * <code>CLOB</code> value
- *
- * @return a stream to which Unicode encoded characters can be written
- * @throws SerialException if the SerialClob is not instantiated with
- * a Clob object that supports <code>setCharacterStream</code>
- * @throws SQLException if there is an error accessing the
- * <code>CLOB</code> value
- * @see #getCharacterStream
- */
- public java.io.Writer setCharacterStream(long pos)
- throws SerialException, SQLException {
- if (this.clob.setCharacterStream(pos) != null) {
- return this.clob.setCharacterStream(pos);
- } else {
- throw new SerialException("Unsupported operation. SerialClob cannot " +
- "return a writable character stream\n unless instantiated with a Clob object " +
- "that has a setCharacterStream implementation");
- }
- }
-
- /**
- * Truncates the <code>CLOB</code> value that this <code>SerialClob</code>
- * object represents so that it has a length of <code>len</code>
- * characters.
- * <p>
- * Truncating a <code>SerialClob</code> object to length 0 has the effect of
- * clearing its contents.
- *
- * @param length the length, in bytes, to which the <code>CLOB</code>
- * value should be truncated
- * @throws SQLException if there is an error accessing the
- * <code>CLOB</code> value
- */
- public void truncate(long length) throws SerialException {
- if (length > len) {
- throw new SerialException
- ("Length more than what can be truncated");
- } else {
- len = length;
- // re-size the buffer
-
- if (len == 0) {
- buf = new char[] {};
- } else {
- buf = (this.getSubString(1, (int)len)).toCharArray();
- }
-
- }
- }
-
-
-
- /**
- * The identifier that assists in the serialization of this <code>SerialClob</code>
- * object.
- */
- static final long serialVersionUID = -1662519690087375313L;
- }