--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/javax/sql/rowset/serial/SQLInputImpl.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,830 @@
+/*
+ * Copyright 2003-2006 Sun Microsystems, Inc. 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. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package javax.sql.rowset.serial;
+
+import java.sql.*;
+import javax.sql.*;
+import java.io.*;
+import java.math.*;
+import java.util.Map;
+
+/**
+ * An input stream used for custom mapping user-defined types (UDTs).
+ * An <code>SQLInputImpl</code> object is an input stream that contains a
+ * stream of values that are the attributes of a UDT.
+ * <p>
+ * This class is used by the driver behind the scenes when the method
+ * <code>getObject</code> is called on an SQL structured or distinct type
+ * that has a custom mapping; a programmer never invokes
+ * <code>SQLInputImpl</code> methods directly. They are provided here as a
+ * convenience for those who write <code>RowSet</code> implementations.
+ * <P>
+ * The <code>SQLInputImpl</code> class provides a set of
+ * reader methods analogous to the <code>ResultSet</code> getter
+ * methods. These methods make it possible to read the values in an
+ * <code>SQLInputImpl</code> object.
+ * <P>
+ * The method <code>wasNull</code> is used to determine whether the
+ * the last value read was SQL <code>NULL</code>.
+ * <P>When the method <code>getObject</code> is called with an
+ * object of a class implementing the interface <code>SQLData</code>,
+ * the JDBC driver calls the method <code>SQLData.getSQLType</code>
+ * to determine the SQL type of the UDT being custom mapped. The driver
+ * creates an instance of <code>SQLInputImpl</code>, populating it with the
+ * attributes of the UDT. The driver then passes the input
+ * stream to the method <code>SQLData.readSQL</code>, which in turn
+ * calls the <code>SQLInputImpl</code> reader methods
+ * to read the attributes from the input stream.
+ * @see java.sql.SQLData
+ */
+public class SQLInputImpl implements SQLInput {
+
+ /**
+ * <code>true</code> if the last value returned was <code>SQL NULL</code>;
+ * <code>false</code> otherwise.
+ */
+ private boolean lastValueWasNull;
+
+ /**
+ * The current index into the array of SQL structured type attributes
+ * that will be read from this <code>SQLInputImpl</code> object and
+ * mapped to the fields of a class in the Java programming language.
+ */
+ private int idx;
+
+ /**
+ * The array of attributes to be read from this stream. The order
+ * of the attributes is the same as the order in which they were
+ * listed in the SQL definition of the UDT.
+ */
+ private Object attrib[];
+
+ /**
+ * The type map to use when the method <code>readObject</code>
+ * is invoked. This is a <code>java.util.Map</code> object in which
+ * there may be zero or more entries. Each entry consists of the
+ * fully qualified name of a UDT (the value to be mapped) and the
+ * <code>Class</code> object for a class that implements
+ * <code>SQLData</code> (the Java class that defines how the UDT
+ * will be mapped).
+ */
+ private Map map;
+
+
+ /**
+ * Creates an <code>SQLInputImpl</code> object initialized with the
+ * given array of attributes and the given type map. If any of the
+ * attributes is a UDT whose name is in an entry in the type map,
+ * the attribute will be mapped according to the corresponding
+ * <code>SQLData</code> implementation.
+ *
+ * @param attributes an array of <code>Object</code> instances in which
+ * each element is an attribute of a UDT. The order of the
+ * attributes in the array is the same order in which
+ * the attributes were defined in the UDT definition.
+ * @param map a <code>java.util.Map</code> object containing zero or more
+ * entries, with each entry consisting of 1) a <code>String</code>
+ * giving the fully
+ * qualified name of the UDT and 2) the <code>Class</code> object
+ * for the <code>SQLData</code> implementation that defines how
+ * the UDT is to be mapped
+ * @throws SQLException if the <code>attributes</code> or the <code>map</code>
+ * is a <code>null</code> value
+ */
+
+ public SQLInputImpl(Object[] attributes, Map<String,Class<?>> map)
+ throws SQLException
+ {
+ if ((attributes == null) || (map == null)) {
+ throw new SQLException("Cannot instantiate a SQLInputImpl " +
+ "object with null parameters");
+ }
+ // assign our local reference to the attribute stream
+ attrib = attributes;
+ // init the index point before the head of the stream
+ idx = -1;
+ // set the map
+ this.map = map;
+ }
+
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as an <code>Object</code> in the Java programming language.
+ *
+ * @return the next value in the input stream
+ * as an <code>Object</code> in the Java programming language
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no further values in the stream
+ */
+ private Object getNextAttribute() throws SQLException {
+ if (++idx >= attrib.length) {
+ throw new SQLException("SQLInputImpl exception: Invalid read " +
+ "position");
+ } else {
+ return attrib[idx];
+ }
+ }
+
+
+ //================================================================
+ // Methods for reading attributes from the stream of SQL data.
+ // These methods correspond to the column-accessor methods of
+ // java.sql.ResultSet.
+ //================================================================
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object as
+ * a <code>String</code> in the Java programming language.
+ * <p>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code>
+ * implementation.
+ * <p>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no further values in the stream.
+ */
+ public String readString() throws SQLException {
+
+ String attrib = (String)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object as
+ * a <code>boolean</code> in the Java programming language.
+ * <p>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code>
+ * implementation.
+ * <p>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no further values in the stream.
+ */
+ public boolean readBoolean() throws SQLException {
+
+ Boolean attrib = (Boolean)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return false;
+ } else {
+ lastValueWasNull = false;
+ return attrib.booleanValue();
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object as
+ * a <code>byte</code> in the Java programming language.
+ * <p>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code>
+ * implementation.
+ * <p>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no further values in the stream
+ */
+ public byte readByte() throws SQLException {
+ Byte attrib = (Byte)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return (byte)0;
+ } else {
+ lastValueWasNull = false;
+ return attrib.byteValue();
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as a <code>short</code> in the Java programming language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public short readShort() throws SQLException {
+ Short attrib = (Short)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return (short)0;
+ } else {
+ lastValueWasNull = false;
+ return attrib.shortValue();
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as an <code>int</code> in the Java programming language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public int readInt() throws SQLException {
+ Integer attrib = (Integer)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return (int)0;
+ } else {
+ lastValueWasNull = false;
+ return attrib.intValue();
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as a <code>long</code> in the Java programming language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public long readLong() throws SQLException {
+ Long attrib = (Long)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return (long)0;
+ } else {
+ lastValueWasNull = false;
+ return attrib.longValue();
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as a <code>float</code> in the Java programming language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public float readFloat() throws SQLException {
+ Float attrib = (Float)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return (float)0;
+ } else {
+ lastValueWasNull = false;
+ return attrib.floatValue();
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as a <code>double</code> in the Java programming language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public double readDouble() throws SQLException {
+ Double attrib = (Double)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return (double)0;
+ } else {
+ lastValueWasNull = false;
+ return attrib.doubleValue();
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as a <code>java.math.BigDecimal</code>.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public java.math.BigDecimal readBigDecimal() throws SQLException {
+ java.math.BigDecimal attrib = (java.math.BigDecimal)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as an array of bytes.
+ * <p>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public byte[] readBytes() throws SQLException {
+ byte[] attrib = (byte[])getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> as
+ * a <code>java.sql.Date</code> object.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type; this responsibility is delegated
+ * to the UDT mapping as defined by a <code>SQLData</code> implementation.
+ * <P>
+ * @return the next attribute in this <code>SQLInputImpl</code> object;
+ * if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position or if there are no more values in the stream
+ */
+ public java.sql.Date readDate() throws SQLException {
+ java.sql.Date attrib = (java.sql.Date)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object as
+ * a <code>java.sql.Time</code> object.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return the attribute; if the value is <code>SQL NULL</code>, return
+ * <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public java.sql.Time readTime() throws SQLException {
+ java.sql.Time attrib = (java.sql.Time)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object as
+ * a <code>java.sql.Timestamp</code> object.
+ *
+ * @return the attribute; if the value is <code>SQL NULL</code>, return
+ * <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public java.sql.Timestamp readTimestamp() throws SQLException {
+ java.sql.Timestamp attrib = (java.sql.Timestamp)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the next attribute in this <code>SQLInputImpl</code> object
+ * as a stream of Unicode characters.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return the attribute; if the value is <code>SQL NULL</code>, return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public java.io.Reader readCharacterStream() throws SQLException {
+ java.io.Reader attrib = (java.io.Reader)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Returns the next attribute in this <code>SQLInputImpl</code> object
+ * as a stream of ASCII characters.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return the attribute; if the value is <code>SQL NULL</code>,
+ * return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public java.io.InputStream readAsciiStream() throws SQLException {
+ java.io.InputStream attrib = (java.io.InputStream)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Returns the next attribute in this <code>SQLInputImpl</code> object
+ * as a stream of uninterpreted bytes.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return the attribute; if the value is <code>SQL NULL</code>, return
+ * <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public java.io.InputStream readBinaryStream() throws SQLException {
+ java.io.InputStream attrib = (java.io.InputStream)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ //================================================================
+ // Methods for reading items of SQL user-defined types from the stream.
+ //================================================================
+
+ /**
+ * Retrieves the value at the head of this <code>SQLInputImpl</code>
+ * object as an <code>Object</code> in the Java programming language. The
+ * actual type of the object returned is determined by the default
+ * mapping of SQL types to types in the Java programming language unless
+ * there is a custom mapping, in which case the type of the object
+ * returned is determined by this stream's type map.
+ * <P>
+ * The JDBC technology-enabled driver registers a type map with the stream
+ * before passing the stream to the application.
+ * <P>
+ * When the datum at the head of the stream is an SQL <code>NULL</code>,
+ * this method returns <code>null</code>. If the datum is an SQL
+ * structured or distinct type with a custom mapping, this method
+ * determines the SQL type of the datum at the head of the stream,
+ * constructs an object of the appropriate class, and calls the method
+ * <code>SQLData.readSQL</code> on that object. The <code>readSQL</code>
+ * method then calls the appropriate <code>SQLInputImpl.readXXX</code>
+ * methods to retrieve the attribute values from the stream.
+ *
+ * @return the value at the head of the stream as an <code>Object</code>
+ * in the Java programming language; <code>null</code> if
+ * the value is SQL <code>NULL</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public Object readObject() throws SQLException {
+ Object attrib = (Object)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ if (attrib instanceof Struct) {
+ Struct s = (Struct)attrib;
+ // look up the class in the map
+ Class c = (Class)map.get(s.getSQLTypeName());
+ if (c != null) {
+ // create new instance of the class
+ SQLData obj = null;
+ try {
+ obj = (SQLData)c.newInstance();
+ } catch (java.lang.InstantiationException ex) {
+ throw new SQLException("Unable to instantiate: " +
+ ex.getMessage());
+ } catch (java.lang.IllegalAccessException ex) {
+ throw new SQLException("Unable to instantiate: " +
+ ex.getMessage());
+ }
+ // get the attributes from the struct
+ Object attribs[] = s.getAttributes(map);
+ // create the SQLInput "stream"
+ SQLInputImpl sqlInput = new SQLInputImpl(attribs, map);
+ // read the values...
+ obj.readSQL(sqlInput, s.getSQLTypeName());
+ return (Object)obj;
+ }
+ }
+ return (Object)attrib;
+ }
+ }
+
+ /**
+ * Retrieves the value at the head of this <code>SQLInputImpl</code> object
+ * as a <code>Ref</code> object in the Java programming language.
+ *
+ * @return a <code>Ref</code> object representing the SQL
+ * <code>REF</code> value at the head of the stream; if the value
+ * is <code>SQL NULL</code> return <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public Ref readRef() throws SQLException {
+ Ref attrib = (Ref)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the <code>BLOB</code> value at the head of this
+ * <code>SQLInputImpl</code> object as a <code>Blob</code> object
+ * in the Java programming language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return a <code>Blob</code> object representing the SQL
+ * <code>BLOB</code> value at the head of this stream;
+ * if the value is <code>SQL NULL</code>, return
+ * <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public Blob readBlob() throws SQLException {
+ Blob attrib = (Blob)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Retrieves the <code>CLOB</code> value at the head of this
+ * <code>SQLInputImpl</code> object as a <code>Clob</code> object
+ * in the Java programming language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return a <code>Clob</code> object representing the SQL
+ * <code>CLOB</code> value at the head of the stream;
+ * if the value is <code>SQL NULL</code>, return
+ * <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public Clob readClob() throws SQLException {
+
+ Clob attrib = (Clob)getNextAttribute();
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Reads an SQL <code>ARRAY</code> value from the stream and
+ * returns it as an <code>Array</code> object in the Java programming
+ * language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return an <code>Array</code> object representing the SQL
+ * <code>ARRAY</code> value at the head of the stream; *
+ * if the value is <code>SQL NULL</code>, return
+ * <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+
+ */
+ public Array readArray() throws SQLException {
+ Array attrib = (Array)getNextAttribute();
+
+ if (attrib == null) {
+ lastValueWasNull = true;
+ return null;
+ } else {
+ lastValueWasNull = false;
+ return attrib;
+ }
+ }
+
+ /**
+ * Ascertains whether the last value read from this
+ * <code>SQLInputImpl</code> object was <code>null</code>.
+ *
+ * @return <code>true</code> if the SQL value read most recently was
+ * <code>null</code>; otherwise, <code>false</code>; by default it
+ * will return false
+ * @throws SQLException if an error occurs determining the last value
+ * read was a <code>null</code> value or not;
+ */
+ public boolean wasNull() throws SQLException {
+ return lastValueWasNull;
+ }
+
+ /**
+ * Reads an SQL <code>DATALINK</code> value from the stream and
+ * returns it as an <code>URL</code> object in the Java programming
+ * language.
+ * <P>
+ * This method does not perform type-safe checking to determine if the
+ * returned type is the expected type as this responsibility is delegated
+ * to the UDT mapping as implemented by a <code>SQLData</code>
+ * implementation.
+ *
+ * @return an <code>URL</code> object representing the SQL
+ * <code>DATALINK</code> value at the head of the stream; *
+ * if the value is <code>SQL NULL</code>, return
+ * <code>null</code>
+ * @throws SQLException if the read position is located at an invalid
+ * position; or if there are no further values in the stream.
+ */
+ public java.net.URL readURL() throws SQLException {
+ throw new SQLException("Operation not supported");
+ }
+
+ //---------------------------- JDBC 4.0 -------------------------
+
+ /**
+ * Reads an SQL <code>NCLOB</code> value from the stream and returns it as a
+ * <code>Clob</code> object in the Java programming language.
+ *
+ * @return a <code>NClob</code> object representing data of the SQL <code>NCLOB</code> value
+ * at the head of the stream; <code>null</code> if the value read is
+ * SQL <code>NULL</code>
+ * @exception SQLException if a database access error occurs
+ */
+ public NClob readNClob() throws SQLException {
+ throw new UnsupportedOperationException("Operation not supported");
+ }
+
+ /**
+ * Reads the next attribute in the stream and returns it as a <code>String</code>
+ * in the Java programming language. It is intended for use when
+ * accessing <code>NCHAR</code>,<code>NVARCHAR</code>
+ * and <code>LONGNVARCHAR</code> columns.
+ *
+ * @return the attribute; if the value is SQL <code>NULL</code>, returns <code>null</code>
+ * @exception SQLException if a database access error occurs
+ */
+ public String readNString() throws SQLException {
+ throw new UnsupportedOperationException("Operation not supported");
+ }
+
+ /**
+ * Reads an SQL <code>XML</code> value from the stream and returns it as a
+ * <code>SQLXML</code> object in the Java programming language.
+ *
+ * @return a <code>SQLXML</code> object representing data of the SQL <code>XML</code> value
+ * at the head of the stream; <code>null</code> if the value read is
+ * SQL <code>NULL</code>
+ * @exception SQLException if a database access error occurs
+ */
+ public SQLXML readSQLXML() throws SQLException {
+ throw new UnsupportedOperationException("Operation not supported");
+ }
+
+ /**
+ * Reads an SQL <code>ROWID</code> value from the stream and returns it as a
+ * <code>RowId</code> object in the Java programming language.
+ *
+ * @return a <code>RowId</code> object representing data of the SQL <code>ROWID</code> value
+ * at the head of the stream; <code>null</code> if the value read is
+ * SQL <code>NULL</code>
+ * @exception SQLException if a database access error occurs
+ */
+ public RowId readRowId() throws SQLException {
+ throw new UnsupportedOperationException("Operation not supported");
+ }
+
+
+}