jdbc4updatableresultset.java

用于JAVA数据库连接.解压就可用,方便得很

	            syncUpdate();
	        }
	
	        ((com.mysql.jdbc.JDBC4PreparedStatement)this.updater).setNString(columnIndex, x);
	    } else {
	    	((com.mysql.jdbc.JDBC4PreparedStatement)this.inserter).setNString(columnIndex, x);
	
	        if (x == null) {
	        	 this.thisRow.setColumnValue(columnIndex, null);
	        } else {
	        	 this.thisRow.setColumnValue(columnIndex, StringUtils.getBytes(x,
	                        this.charConverter, fieldEncoding,
	                        this.connection.getServerCharacterEncoding(),
	                        this.connection.parserKnowsUnicode()));
	        }
	    }
	}

	/**
	 * JDBC 4.0 Update a column with NATIONAL CHARACTER. The updateXXX() methods
	 * are used to update column values in the current row, or the insert row.
	 * The updateXXX() methods do not update the underlying database, instead
	 * the updateRow() or insertRow() methods are called to update the database.
	 * 
	 * @param columnName
	 *            the name of the column
	 * @param x
	 *            the new column value
	 * 
	 * @exception SQLException
	 *                if a database-access error occurs
	 */
	public synchronized void updateNString(String columnName, String x)
	        throws SQLException {
	    updateNString(findColumn(columnName), x);
	}

	public int getHoldability() throws SQLException {
		throw new NotYetImplementedException();
	}

	/**
	 * JDBC 4.0 Get a NCLOB column.
	 * 
	 * @param columnIndex
	 *            the first column is 1, the second is 2, ...
	 * 
	 * @return an object representing a NCLOB
	 * 
	 * @throws SQLException
	 *             if an error occurs
	 */
	protected java.sql.NClob getNativeNClob(int columnIndex)
			throws SQLException {
		String stringVal = getStringForNClob(columnIndex);
	
		if (stringVal == null) {
			return null;
		}
	
		return getNClobFromString(stringVal, columnIndex);
	}

	/**
	 * JDBC 4.0
	 * 
	 * <p>
	 * Get the value of a column in the current row as a java.io.Reader.
	 * </p>
	 * 
	 * @param columnIndex
	 *            the column to get the value from
	 * 
	 * @return the value in the column as a java.io.Reader.
	 * 
	 * @throws SQLException
	 *             if an error occurs
	 */
	public Reader getNCharacterStream(int columnIndex) throws SQLException {
		String fieldEncoding = this.fields[columnIndex - 1].getCharacterSet();
		if (fieldEncoding == null || !fieldEncoding.equals("UTF-8")) {
			throw new SQLException(
					"Can not call getNCharacterStream() when field's charset isn't UTF-8");
		}
		
		return getCharacterStream(columnIndex);
	}

	/**
	 * JDBC 4.0
	 * 
	 * <p>
	 * Get the value of a column in the current row as a java.io.Reader.
	 * </p>
	 * 
	 * @param columnName
	 *            the column name to retrieve the value from
	 * 
	 * @return the value as a java.io.Reader
	 * 
	 * @throws SQLException
	 *             if an error occurs
	 */
	public Reader getNCharacterStream(String columnName) throws SQLException {
		return getNCharacterStream(findColumn(columnName));
	}

	/**
	 * JDBC 4.0 Get a NCLOB column.
	 * 
	 * @param i
	 *            the first column is 1, the second is 2, ...
	 * 
	 * @return an object representing a NCLOB
	 * 
	 * @throws SQLException
	 *             if an error occurs
	 */
	public NClob getNClob(int columnIndex) throws SQLException {
		String fieldEncoding = this.fields[columnIndex - 1].getCharacterSet();
		
		if (fieldEncoding == null || !fieldEncoding.equals("UTF-8")) {
			throw new SQLException(
					"Can not call getNClob() when field's charset isn't UTF-8");
		}
		
		if (!this.isBinaryEncoded) {
			String asString = getStringForNClob(columnIndex);
	
			if (asString == null) {
				return null;
			}
	
			return new com.mysql.jdbc.JDBC4NClob(asString);
		}
	
		return getNativeNClob(columnIndex);
	}

	/**
	 * JDBC 4.0 Get a NCLOB column.
	 * 
	 * @param colName
	 *            the column name
	 * 
	 * @return an object representing a NCLOB
	 * 
	 * @throws SQLException
	 *             if an error occurs
	 */
	public NClob getNClob(String columnName) throws SQLException {
		return getNClob(findColumn(columnName));
	}

	private final java.sql.NClob getNClobFromString(String stringVal,
			int columnIndex) throws SQLException {
		return new com.mysql.jdbc.JDBC4NClob(stringVal);
	}

	/**
	 * JDBC 4.0
	 * 
	 * Get the value of a column in the current row as a Java String
	 * 
	 * @param columnIndex
	 *            the first column is 1, the second is 2...
	 * 
	 * @return the column value, null for SQL NULL
	 * 
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public String getNString(int columnIndex) throws SQLException {
		String fieldEncoding = this.fields[columnIndex - 1].getCharacterSet();
		
		if (fieldEncoding == null || !fieldEncoding.equals("UTF-8")) {
			throw new SQLException(
					"Can not call getNString() when field's charset isn't UTF-8");
		}
		
		return getString(columnIndex);
	}

	/**
	 * JDBC 4.0
	 * 
	 * The following routines simply convert the columnName into a columnIndex
	 * and then call the appropriate routine above.
	 * 
	 * @param columnName
	 *            is the SQL name of the column
	 * 
	 * @return the column value
	 * 
	 * @exception SQLException
	 *                if a database access error occurs
	 */
	public String getNString(String columnName) throws SQLException {
		return getNString(findColumn(columnName));
	}

	public RowId getRowId(int columnIndex) throws SQLException {
		throw new NotYetImplementedException();
	}

	public RowId getRowId(String columnLabel) throws SQLException {
		return getRowId(findColumn(columnLabel));
	}

	public SQLXML getSQLXML(int columnIndex) throws SQLException {
		return new JDBC4MysqlSQLXML(this, columnIndex);
	}

	public SQLXML getSQLXML(String columnLabel) throws SQLException {
		return getSQLXML(findColumn(columnLabel));
	}

	private String getStringForNClob(int columnIndex) throws SQLException {
		String asString = null;
	
		String forcedEncoding = "UTF-8";
	
		try {
			byte[] asBytes = null;
	
			if (!this.isBinaryEncoded) {
				asBytes = getBytes(columnIndex);
			} else {
				asBytes = getNativeBytes(columnIndex, true);
			}
	
			if (asBytes != null) {
				asString = new String(asBytes, forcedEncoding);
			}
		} catch (UnsupportedEncodingException uee) {
			throw SQLError.createSQLException("Unsupported character encoding "
					+ forcedEncoding, SQLError.SQL_STATE_ILLEGAL_ARGUMENT);
		}
	
		return asString;
	}

	public synchronized boolean isClosed() throws SQLException {
		return this.isClosed;
	}

	/**
	 * Returns true if this either implements the interface argument or is
	 * directly or indirectly a wrapper for an object that does. Returns false
	 * otherwise. If this implements the interface then return true, else if
	 * this is a wrapper then return the result of recursively calling
	 * <code>isWrapperFor</code> on the wrapped object. If this does not
	 * implement the interface and is not a wrapper, return false. This method
	 * should be implemented as a low-cost operation compared to
	 * <code>unwrap</code> so that callers can use this method to avoid
	 * expensive <code>unwrap</code> calls that may fail. If this method
	 * returns true then calling <code>unwrap</code> with the same argument
	 * should succeed.
	 * 
	 * @param interfaces
	 *            a Class defining an interface.
	 * @return true if this implements the interface or directly or indirectly
	 *         wraps an object that does.
	 * @throws java.sql.SQLException
	 *             if an error occurs while determining whether this is a
	 *             wrapper for an object with the given interface.
	 * @since 1.6
	 */
	public boolean isWrapperFor(Class<?> iface) throws SQLException {
		checkClosed();
		
		// This works for classes that aren't actually wrapping
		// anything
		return iface.isInstance(this);
	}

    /**
	 * 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 <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);
        }
    }
}