/**
* Returns an object that implements the given interface to allow access to non-standard methods,
* or standard methods not exposed by the proxy. The result may be either the object found to
* implement the interface or a proxy for that object. If the receiver implements the interface
* then that is the object. If the receiver is a wrapper and the wrapped object implements the
* interface then that is the object. Otherwise the object is the result of calling <code>unwrap
* </code> recursively on the wrapped object. If the receiver is not a wrapper and does not
* implement the interface, then an <code>SQLException</code> is thrown.
*
* @param iface A Class defining an interface that the result must implement.
* @return an object that implements the interface. May be a proxy for the actual implementing
* object.
* @throws java.sql.SQLException If no object found that implements the interface
* @since 1.6
*/
public synchronized <T> T unwrap(java.lang.Class<T> iface) throws java.sql.SQLException {
try {
if ("java.sql.Statement".equals(iface.getName())
|| "java.sql.PreparedStatement".equals(iface.getName())
|| "java.sql.Wrapper.class".equals(iface.getName())) {
return iface.cast(this);
}
if (unwrappedInterfaces == null) {
unwrappedInterfaces = new HashMap();
}
Object cachedUnwrapped = unwrappedInterfaces.get(iface);
if (cachedUnwrapped == null) {
if (cachedUnwrapped == null) {
cachedUnwrapped =
Proxy.newProxyInstance(
this.wrappedStmt.getClass().getClassLoader(),
new Class[] {iface},
new ConnectionErrorFiringInvocationHandler(this.wrappedStmt));
unwrappedInterfaces.put(iface, cachedUnwrapped);
}
unwrappedInterfaces.put(iface, cachedUnwrapped);
}
return iface.cast(cachedUnwrapped);
} catch (ClassCastException cce) {
throw SQLError.createSQLException(
"Unable to unwrap to " + iface.toString(),
SQLError.SQL_STATE_ILLEGAL_ARGUMENT,
this.exceptionInterceptor);
}
}
/**
* Returns <code>this</code> if this class implements the interface
*
* @param interfaces a Class defining an interface
* @return an object that implements the interface
* @throws java.sql.SQLException if no object if found that implements the interface
*/
public <T> T unwrap(java.lang.Class<T> interfaces) throws SQLException {
try {
return interfaces.cast(this);
} catch (ClassCastException cce) {
throw new SqlException(null, new ClientMessageId(SQLState.UNABLE_TO_UNWRAP), interfaces)
.getSQLException();
}
}
/**
* Returns <code>this</code> if this class implements the interface
*
* @param interfaces a Class defining an interface
* @return an object that implements the interface
* @throws java.sql.SQLExption if no object if found that implements the interface
*/
public <T> T unwrap(java.lang.Class<T> interfaces) throws SQLException {
checkStatus();
try {
return interfaces.cast(this);
} catch (ClassCastException cce) {
throw newSQLException(SQLState.UNABLE_TO_UNWRAP, interfaces);
}
}
public <T> T unwrap(java.lang.Class<T> iface) throws java.sql.SQLException {
try {
// This works for classes that aren't actually wrapping anything
return iface.cast(this);
} catch (ClassCastException cce) {
throw SQLError.createSQLException("Unable to unwrap to " + iface.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
}
}
/**
* Returns <code>this</code> if this class implements the interface
*
* @param interfaces a Class defining an interface
* @return an object that implements the interface
* @throws java.sql.SQLExption if no object if found that implements the interface
*/
public final <T> T unwrap(java.lang.Class<T> interfaces) throws SQLException {
try {
if (getRealConnection().isClosed()) throw Util.noCurrentConnection();
// Derby does not implement non-standard methods on
// JDBC objects
try {
return interfaces.cast(this);
} catch (ClassCastException cce) {
throw Util.generateCsSQLException(SQLState.UNABLE_TO_UNWRAP, interfaces);
}
} catch (SQLException sqle) {
notifyException(sqle);
throw sqle;
}
}
private static <T> T __check_arg__(java.lang.Class<T> expectedClass, Object argument) {
T result = null;
if (java.lang.Integer.class.equals(expectedClass) && argument instanceof Double) {
result = (T) new java.lang.Integer(((Double) argument).intValue());
} else if (java.lang.Float.class.equals(expectedClass) && argument instanceof Double) {
result = (T) new java.lang.Float(((Double) argument).floatValue());
} else {
try {
result = expectedClass.cast(argument);
} catch (Throwable ex) {
throw new IllegalArgumentException(
String.format(
"Bad parameter type in call to %s. Found '%s' when expected '%s'.",
"nbActions", argument.getClass().getName(), expectedClass.getName()));
}
}
return result;
}
