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* Copyright (c) 1998, 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
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package java.sql;
/**
* An input stream that contains a stream of values representing an
* instance of an SQL structured type or an SQL distinct type.
* This interface, used only for custom mapping, is used by the driver
* behind the scenes, and a programmer never directly invokes
* SQLInput
methods. The reader methods
* (readLong
, readBytes
, and so on)
* provide a way for an implementation of the SQLData
* interface to read the values in an SQLInput
object.
* And as described in SQLData
, calls to reader methods must
* be made in the order that their corresponding attributes appear in the
* SQL definition of the type.
* The method wasNull
is used to determine whether
* the last value read was SQL NULL
.
*
When the method getObject
is called with an
* object of a class implementing the interface SQLData
,
* the JDBC driver calls the method SQLData.getSQLType
* to determine the SQL type of the user-defined type (UDT)
* being custom mapped. The driver
* creates an instance of SQLInput
, populating it with the
* attributes of the UDT. The driver then passes the input
* stream to the method SQLData.readSQL
, which in turn
* calls the SQLInput
reader methods
* in its implementation for reading the
* attributes from the input stream.
* @since 1.2
*/
public interface SQLInput {
//================================================================
// Methods for reading attributes from the stream of SQL data.
// These methods correspond to the column-accessor methods of
// java.sql.ResultSet.
//================================================================
/**
* Reads the next attribute in the stream and returns it as a String
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
String readString() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a boolean
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns false
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
boolean readBoolean() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a byte
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns 0
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
byte readByte() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a short
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns 0
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
short readShort() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as an int
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns 0
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
int readInt() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a long
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns 0
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
long readLong() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a float
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns 0
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
float readFloat() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a double
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns 0
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
double readDouble() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a java.math.BigDecimal
* object in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
java.math.BigDecimal readBigDecimal() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as an array of bytes
* in the Java programming language.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
byte[] readBytes() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a java.sql.Date
object.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
java.sql.Date readDate() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a java.sql.Time
object.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
java.sql.Time readTime() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a java.sql.Timestamp
object.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
java.sql.Timestamp readTimestamp() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a stream of Unicode characters.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
java.io.Reader readCharacterStream() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a stream of ASCII characters.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
java.io.InputStream readAsciiStream() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a stream of uninterpreted
* bytes.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
java.io.InputStream readBinaryStream() throws SQLException;
//================================================================
// Methods for reading items of SQL user-defined types from the stream.
//================================================================
/**
* Reads the datum at the head of the stream and returns it as an
* Object
in the Java programming language. The
* actual type of the object returned is determined by the default type
* mapping, and any customizations present in this stream's type map.
*
*
A type map is registered with the stream by the JDBC driver before the * stream is passed to the application. * *
When the datum at the head of the stream is an SQL NULL
,
* the method returns null
. If the datum is an SQL structured or distinct
* type, it determines the SQL type of the datum at the head of the stream.
* If the stream's type map has an entry for that SQL type, the driver
* constructs an object of the appropriate class and calls the method
* SQLData.readSQL
on that object, which reads additional data from the
* stream, using the protocol described for that method.
*
* @return the datum at the head of the stream as an Object
in the
* Java programming language;null
if the datum is SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
Object readObject() throws SQLException;
/**
* Reads an SQL REF
value from the stream and returns it as a
* Ref
object in the Java programming language.
*
* @return a Ref
object representing the SQL REF
value
* at the head of the stream; null
if the value read is
* SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
Ref readRef() throws SQLException;
/**
* Reads an SQL BLOB
value from the stream and returns it as a
* Blob
object in the Java programming language.
*
* @return a Blob
object representing data of the SQL BLOB
value
* at the head of the stream; null
if the value read is
* SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
Blob readBlob() throws SQLException;
/**
* Reads an SQL CLOB
value from the stream and returns it as a
* Clob
object in the Java programming language.
*
* @return a Clob
object representing data of the SQL CLOB
value
* at the head of the stream; null
if the value read is
* SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
Clob readClob() throws SQLException;
/**
* Reads an SQL ARRAY
value from the stream and returns it as an
* Array
object in the Java programming language.
*
* @return an Array
object representing data of the SQL
* ARRAY
value at the head of the stream; null
* if the value read is SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
Array readArray() throws SQLException;
/**
* Retrieves whether the last value read was SQL NULL
.
*
* @return true
if the most recently read SQL value was SQL
* NULL
; false
otherwise
* @exception SQLException if a database access error occurs
*
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.2
*/
boolean wasNull() throws SQLException;
//---------------------------- JDBC 3.0 -------------------------
/**
* Reads an SQL DATALINK
value from the stream and returns it as a
* java.net.URL
object in the Java programming language.
*
* @return a java.net.URL
object.
* @exception SQLException if a database access error occurs,
* or if a URL is malformed
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.4
*/
java.net.URL readURL() throws SQLException;
//---------------------------- JDBC 4.0 -------------------------
/**
* Reads an SQL NCLOB
value from the stream and returns it as a
* NClob
object in the Java programming language.
*
* @return a NClob
object representing data of the SQL NCLOB
value
* at the head of the stream; null
if the value read is
* SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.6
*/
NClob readNClob() throws SQLException;
/**
* Reads the next attribute in the stream and returns it as a String
* in the Java programming language. It is intended for use when
* accessing NCHAR
,NVARCHAR
* and LONGNVARCHAR
columns.
*
* @return the attribute; if the value is SQL NULL
, returns null
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.6
*/
String readNString() throws SQLException;
/**
* Reads an SQL XML
value from the stream and returns it as a
* SQLXML
object in the Java programming language.
*
* @return a SQLXML
object representing data of the SQL XML
value
* at the head of the stream; null
if the value read is
* SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.6
*/
SQLXML readSQLXML() throws SQLException;
/**
* Reads an SQL ROWID
value from the stream and returns it as a
* RowId
object in the Java programming language.
*
* @return a RowId
object representing data of the SQL ROWID
value
* at the head of the stream; null
if the value read is
* SQL NULL
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.6
*/
RowId readRowId() throws SQLException;
//--------------------------JDBC 4.2 -----------------------------
/**
* Reads the next attribute in the stream and returns it as an
* {@code Object} in the Java programming language. The
* actual type of the object returned is determined by the specified
* Java data type, and any customizations present in this
* stream's type map.
*
*
A type map is registered with the stream by the JDBC driver before the * stream is passed to the application. * *
When the attribute at the head of the stream is an SQL {@code NULL} * the method returns {@code null}. If the attribute is an SQL * structured or distinct * type, it determines the SQL type of the attribute at the head of the stream. * If the stream's type map has an entry for that SQL type, the driver * constructs an object of the appropriate class and calls the method * {@code SQLData.readSQL} on that object, which reads additional data from the * stream, using the protocol described for that method. *
* The default implementation will throw {@code SQLFeatureNotSupportedException}
*
* @param type Class representing the Java data type to convert the attribute to.
* @return the attribute at the head of the stream as an {@code Object} in the
* Java programming language;{@code null} if the attribute is SQL {@code NULL}
* @exception SQLException if a database access error occurs
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.8
*/
default