SQLInputImpl object is an input stream that contains a
* stream of values that are the attributes of a UDT.
*
* This class is used by the driver behind the scenes when the method
* getObject is called on an SQL structured or distinct type
* that has a custom mapping; a programmer never invokes
* SQLInputImpl methods directly. They are provided here as a
* convenience for those who write RowSet implementations.
*
* The SQLInputImpl class provides a set of
* reader methods analogous to the ResultSet getter
* methods. These methods make it possible to read the values in an
* SQLInputImpl object.
*
* The method wasNull is used to determine whether the
* the last value read was SQL NULL.
*
When the method
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* @return the next attribute in this
* 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
* 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
* 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
* 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
* The JDBC technology-enabled driver registers a type map with the stream
* before passing the stream to the application.
*
* When the datum at the head of the stream is an SQL
* 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
* 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
* 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
* 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 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 UDT being custom mapped. The driver
* creates an instance of SQLInputImpl, 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 SQLInputImpl reader methods
* to read the attributes from the input stream.
* @see java.sql.SQLData
*/
public class SQLInputImpl implements SQLInput {
/**
* true if the last value returned was SQL NULL;
* false otherwise.
*/
private boolean lastValueWasNull;
/**
* The current index into the array of SQL structured type attributes
* that will be read from this SQLInputImpl 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 readObject
* is invoked. This is a java.util.Map 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
* Class object for a class that implements
* SQLData (the Java class that defines how the UDT
* will be mapped).
*/
private Map map;
/**
* Creates an SQLInputImpl 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
* SQLData implementation.
*
* @param attributes an array of Object 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 java.util.Map object containing zero or more
* entries, with each entry consisting of 1) a String
* giving the fully
* qualified name of the UDT and 2) the Class object
* for the SQLData implementation that defines how
* the UDT is to be mapped
* @throws SQLException if the attributes or the map
* is a null value
*/
public SQLInputImpl(Object[] attributes, MapSQLInputImpl object
* as an Object in the Java programming language.
*
* @return the next value in the input stream
* as an Object 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 SQLInputImpl object as
* a String in the Java programming language.
* SQLData
* implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object as
* a boolean in the Java programming language.
* SQLData
* implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object as
* a byte in the Java programming language.
* SQLData
* implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as a short in the Java programming language.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as an int in the Java programming language.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as a long in the Java programming language.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as a float in the Java programming language.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as a double in the Java programming language.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as a java.math.BigDecimal.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as an array of bytes.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl as
* a java.sql.Date object.
* SQLData implementation.
* SQLInputImpl object;
* if the value is SQL NULL, return null
* @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 SQLInputImpl object as
* a java.sql.Time object.
* SQLData
* implementation.
*
* @return the attribute; if the value is SQL NULL, return
* null
* @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 SQLInputImpl object as
* a java.sql.Timestamp object.
*
* @return the attribute; if the value is SQL NULL, return
* null
* @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 SQLInputImpl object
* as a stream of Unicode characters.
* SQLData
* implementation.
*
* @return the attribute; if the value is SQL NULL, return null
* @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 SQLInputImpl object
* as a stream of ASCII characters.
* SQLData
* implementation.
*
* @return the attribute; if the value is SQL NULL,
* return null
* @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 SQLInputImpl object
* as a stream of uninterpreted bytes.
* SQLData
* implementation.
*
* @return the attribute; if the value is SQL NULL, return
* null
* @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 SQLInputImpl
* object as an Object 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.
* NULL,
* this method returns null. 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
* SQLData.readSQL on that object. The readSQL
* method then calls the appropriate SQLInputImpl.readXXX
* methods to retrieve the attribute values from the stream.
*
* @return the value at the head of the stream as an Object
* in the Java programming language; null if
* the value is SQL NULL
* @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 SQLInputImpl object
* as a Ref object in the Java programming language.
*
* @return a Ref object representing the SQL
* REF value at the head of the stream; if the value
* is SQL NULL return null
* @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 BLOB value at the head of this
* SQLInputImpl object as a Blob object
* in the Java programming language.
* SQLData
* implementation.
*
* @return a Blob object representing the SQL
* BLOB value at the head of this stream;
* if the value is SQL NULL, return
* null
* @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 CLOB value at the head of this
* SQLInputImpl object as a Clob object
* in the Java programming language.
* SQLData
* implementation.
*
* @return a Clob object representing the SQL
* CLOB value at the head of the stream;
* if the value is SQL NULL, return
* null
* @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 ARRAY value from the stream and
* returns it as an Array object in the Java programming
* language.
* SQLData
* implementation.
*
* @return an Array object representing the SQL
* ARRAY value at the head of the stream; *
* if the value is SQL NULL, return
* null
* @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
* SQLInputImpl object was null.
*
* @return true if the SQL value read most recently was
* null; otherwise, false; by default it
* will return false
* @throws SQLException if an error occurs determining the last value
* read was a null value or not;
*/
public boolean wasNull() throws SQLException {
return lastValueWasNull;
}
/**
* Reads an SQL DATALINK value from the stream and
* returns it as an URL object in the Java programming
* language.
* SQLData
* implementation.
*
* @return an URL object representing the SQL
* DATALINK value at the head of the stream; *
* if the value is SQL NULL, return
* null
* @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 NCLOB value from the stream and returns it as a
* Clob 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
*/
public NClob readNClob() throws SQLException {
throw new UnsupportedOperationException("Operation not supported");
}
/**
* 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
*/
public String readNString() throws SQLException {
throw new UnsupportedOperationException("Operation not supported");
}
/**
* 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
*/
public SQLXML readSQLXML() throws SQLException {
throw new UnsupportedOperationException("Operation not supported");
}
/**
* 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
*/
public RowId readRowId() throws SQLException {
throw new UnsupportedOperationException("Operation not supported");
}
}