A wrapper for Java result set. The wrapper fetches all data and stores it but provides the same interface as a result set without having to keep the DB session open

VirtualResultSet.java

package amp.util.db;

import java.io.InputStream;
import java.io.Reader;
import java.math.BigDecimal;
import java.net.URL;
import java.sql.Array;
import java.sql.Blob;
import java.sql.Clob;
import java.sql.Date;
import java.sql.NClob;
import java.sql.Ref;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.RowId;
import java.sql.SQLException;
import java.sql.SQLWarning;
import java.sql.SQLXML;
import java.sql.Statement;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.Calendar;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

public class VirtualResultSet implements ResultSet {

	private final int COLUMNS;

	private final Iterator<Object> rowIterator;

	private Object[] currentRowObjects;

	private String[] columnNames;

	private final List<Object> resultList;

	public VirtualResultSet(ResultSet resultSet) {
		int columns = 0;
		if (resultSet instanceof VirtualResultSet) {
			VirtualResultSet parent = (VirtualResultSet) resultSet;
			columns = parent.COLUMNS;
			columnNames = parent.columnNames;
			resultList = parent.resultList;
		} else {
			resultList = new LinkedList<Object>();
			try {
				ResultSetMetaData meta = resultSet.getMetaData();
				columns = meta.getColumnCount();

				columnNames = new String[columns];
				for (int index = 0; index < columns; index++) {
					columnNames[index] = meta.getColumnName(index + 1);
				}
				while (resultSet.next()) {
					Object[] resultObjects = new Object[columns];
					for (int index = 0; index < columns; index++) {
						resultObjects[index] = resultSet.getObject(index + 1);
					}
					resultList.add(resultObjects);
				}
			} catch (SQLException e) {
				// no op
			}
		}
		COLUMNS = columns;
		rowIterator = resultList.iterator();
	}

	public VirtualResultSet() {
		COLUMNS = 0;
		resultList = new LinkedList<Object>();
		rowIterator = resultList.iterator();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.sql.ResultSet#next()
	 */
	public boolean next() throws SQLException {
		if (rowIterator.hasNext()) {
			currentRowObjects = (Object[]) rowIterator.next();
			return true;
		} else {
			return false;
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.sql.ResultSet#close()
	 */
	public void close() throws SQLException {
		// no-op
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.sql.ResultSet#wasNull()
	 */
	public boolean wasNull() throws SQLException {
		throw new Error("Unsupported");
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.sql.ResultSet#getString(int)
	 */
	public String getString(int columnIndex) throws SQLException {
		if ( currentRowObjects[columnIndex - 1] == null ) {
			return "";
		} else {
			return currentRowObjects[columnIndex - 1].toString();
		}
	}

    public boolean getBoolean(int columnIndex) throws SQLException {
        final String text = getString(columnIndex);
        if ( text == null ) {
        	return false;
        }
        if ( text.equals("1") || text.toLowerCase().startsWith("t") ) {
                return true;
        } else {
                return false;
        }
    }


	public byte getByte(int columnIndex) throws SQLException {
		byte[] bytes = getString(columnIndex).getBytes();
		if (bytes.length >= 1) {
			return bytes[0];
		}
		throw new SQLException("Not enough bytes");
	}

	public short getShort(int columnIndex) throws SQLException {
		return Short.valueOf(getString(columnIndex)).shortValue();
	}

	public int getInt(int columnIndex) throws SQLException {
		try {
			return Integer.valueOf(getString(columnIndex)).intValue();
		} catch (NumberFormatException e) {
			return 0;
		}
	}

	public long getLong(int columnIndex) throws SQLException {
		return Long.valueOf(getString(columnIndex)).longValue();
	}

	public float getFloat(int columnIndex) throws SQLException {
		return Float.valueOf(getString(columnIndex)).floatValue();
	}

	public double getDouble(int columnIndex) throws SQLException {
		return Double.valueOf(getString(columnIndex)).doubleValue();
	}

	public BigDecimal getBigDecimal(int columnIndex, int scale) throws SQLException {
		throw new Error("Unsupported");
	}

	public byte[] getBytes(int columnIndex) throws SQLException {
		return getString(columnIndex).getBytes();
	}

	public Date getDate(int columnIndex) throws SQLException {
		Object result = getObject(columnIndex);
		if ( result instanceof Date || result == null ) {
			return (Date) result;
		}
		if ( result instanceof Timestamp ) {
			return new Date(((Timestamp) result).getTime());
		}
		throw new Error("Unsupported conversion");
	}

	public Time getTime(int columnIndex) throws SQLException {
		Object result = getObject(columnIndex);
		if ( result instanceof Time || result == null)  {
			return (Time) result;
		}
		if ( result instanceof Timestamp)  {
			return new Time(((Timestamp) result).getTime());
		}
		throw new Error("Unsupported conversion");
	}

	public Timestamp getTimestamp(int columnIndex) throws SQLException {
		Object result = getObject(columnIndex);
		if ( result instanceof Timestamp || result == null ) {
			return (Timestamp) result;
		}
		throw new Error("Unsupported conversion");
	}

	public InputStream getAsciiStream(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public InputStream getUnicodeStream(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public InputStream getBinaryStream(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public String getString(String columnName) throws SQLException {
		return getString(findColumn(columnName));
	}

	public boolean getBoolean(String columnName) throws SQLException {
		return getBoolean(findColumn(columnName));
	}

	public byte getByte(String columnName) throws SQLException {
		return getByte(findColumn(columnName));
	}

	public short getShort(String columnName) throws SQLException {
		return getShort(findColumn(columnName));
	}

	public int getInt(String columnName) throws SQLException {
		return getInt(findColumn(columnName));
	}

	public long getLong(String columnName) throws SQLException {
		return getLong(findColumn(columnName));
	}

	public float getFloat(String columnName) throws SQLException {
		return getFloat(findColumn(columnName));
	}

	public double getDouble(String columnName) throws SQLException {
		return getDouble(findColumn(columnName));
	}

	public BigDecimal getBigDecimal(String columnName, int scale) throws SQLException {
		throw new Error("Unsupported");
	}

	public byte[] getBytes(String columnName) throws SQLException {
		return getBytes(findColumn(columnName));
	}

	public Date getDate(String columnName) throws SQLException {
		return getDate(findColumn(columnName));
	}

	public Time getTime(String columnName) throws SQLException {
		return getTime(findColumn(columnName));
	}

	public Timestamp getTimestamp(String columnName) throws SQLException {
		return getTimestamp(findColumn(columnName));
	}

	public InputStream getAsciiStream(String columnName) throws SQLException {
		throw new Error("Unsupported");
	}

	public InputStream getUnicodeStream(String columnName) throws SQLException {
		throw new Error("Unsupported");
	}

	public InputStream getBinaryStream(String columnName) throws SQLException {
		throw new Error("Unsupported");
	}

	public SQLWarning getWarnings() throws SQLException {
		throw new Error("Unsupported");
	}

	public void clearWarnings() throws SQLException {
		throw new Error("Unsupported");
	}

	public String getCursorName() throws SQLException {
		throw new Error("Unsupported");
	}

	public ResultSetMetaData getMetaData() throws SQLException {
		throw new Error("Unsupported");
	}

	public Object getObject(int columnIndex) throws SQLException {
		return currentRowObjects[columnIndex - 1];
	}

	public Object getObject(String columnName) throws SQLException {
		return currentRowObjects[findColumn(columnName)];
	}

	public int findColumn(String columnName) throws SQLException {
		for (int index = 0; index < COLUMNS; index++) {
			if (columnNames[index].equalsIgnoreCase(columnName)) {
				return index + 1;
			}
		}
		throw new SQLException("Unknown column '" + columnName + '"');
	}

	public Reader getCharacterStream(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public Reader getCharacterStream(String columnName) throws SQLException {
		throw new Error("Unsupported");
	}

	public BigDecimal getBigDecimal(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public BigDecimal getBigDecimal(String columnName) throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean isBeforeFirst() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean isAfterLast() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean isFirst() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean isLast() throws SQLException {
		throw new Error("Unsupported");
	}

	public void beforeFirst() throws SQLException {
		throw new Error("Unsupported");
	}

	public void afterLast() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean first() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean last() throws SQLException {
		throw new Error("Unsupported");
	}

	public int getRow() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean absolute(int row) throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean relative(int rows) throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean previous() throws SQLException {
		throw new Error("Unsupported");
	}

	public void setFetchDirection(int direction) throws SQLException {
		throw new Error("Unsupported");
	}

	public int getFetchDirection() throws SQLException {
		throw new Error("Unsupported");
	}

	public void setFetchSize(int rows) throws SQLException {
		throw new Error("Unsupported");
	}

	public int getFetchSize() throws SQLException {
		throw new Error("Unsupported");
	}

	public int getType() throws SQLException {
		throw new Error("Unsupported");
	}

	public int getConcurrency() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean rowUpdated() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean rowInserted() throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean rowDeleted() throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNull(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBoolean(int columnIndex, boolean x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateByte(int columnIndex, byte x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateShort(int columnIndex, short x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateInt(int columnIndex, int x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateLong(int columnIndex, long x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateFloat(int columnIndex, float x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateDouble(int columnIndex, double x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBigDecimal(int columnIndex, BigDecimal x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateString(int columnIndex, String x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBytes(int columnIndex, byte[] x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateDate(int columnIndex, Date x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateTime(int columnIndex, Time x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateTimestamp(int columnIndex, Timestamp x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateAsciiStream(int columnIndex, InputStream x, int length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBinaryStream(int columnIndex, InputStream x, int length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateCharacterStream(int columnIndex, Reader x, int length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateObject(int columnIndex, Object x, int scale) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateObject(int columnIndex, Object x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNull(String columnName) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBoolean(String columnName, boolean x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateByte(String columnName, byte x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateShort(String columnName, short x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateInt(String columnName, int x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateLong(String columnName, long x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateFloat(String columnName, float x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateDouble(String columnName, double x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBigDecimal(String columnName, BigDecimal x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateString(String columnName, String x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBytes(String columnName, byte[] x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateDate(String columnName, Date x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateTime(String columnName, Time x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateTimestamp(String columnName, Timestamp x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateAsciiStream(String columnName, InputStream x, int length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBinaryStream(String columnName, InputStream x, int length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateCharacterStream(String columnName, Reader reader, int length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateObject(String columnName, Object x, int scale) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateObject(String columnName, Object x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void insertRow() throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateRow() throws SQLException {
		throw new Error("Unsupported");
	}

	public void deleteRow() throws SQLException {
		throw new Error("Unsupported");
	}

	public void refreshRow() throws SQLException {
		throw new Error("Unsupported");
	}

	public void cancelRowUpdates() throws SQLException {
		throw new Error("Unsupported");
	}

	public void moveToInsertRow() throws SQLException {
		throw new Error("Unsupported");
	}

	public void moveToCurrentRow() throws SQLException {
		throw new Error("Unsupported");
	}

	public Statement getStatement() throws SQLException {
		throw new Error("Unsupported");
	}

	public Ref getRef(int i) throws SQLException {
		throw new Error("Unsupported");
	}

	public Blob getBlob(int i) throws SQLException {
		throw new Error("Unsupported");
	}

	public Clob getClob(int i) throws SQLException {
		throw new Error("Unsupported");
	}

	public Array getArray(int i) throws SQLException {
		throw new Error("Unsupported");
	}

	public Ref getRef(String colName) throws SQLException {
		throw new Error("Unsupported");
	}

	public Blob getBlob(String colName) throws SQLException {
		throw new Error("Unsupported");
	}

	public Clob getClob(String colName) throws SQLException {
		throw new Error("Unsupported");
	}

	public Array getArray(String colName) throws SQLException {
		throw new Error("Unsupported");
	}

	public Date getDate(int columnIndex, Calendar cal) throws SQLException {
		throw new Error("Unsupported");
	}

	public Date getDate(String columnName, Calendar cal) throws SQLException {
		throw new Error("Unsupported");
	}

	public Time getTime(int columnIndex, Calendar cal) throws SQLException {
		throw new Error("Unsupported");
	}

	public Time getTime(String columnName, Calendar cal) throws SQLException {
		throw new Error("Unsupported");
	}

	public Timestamp getTimestamp(int columnIndex, Calendar cal) throws SQLException {
		throw new Error("Unsupported");
	}

	public Timestamp getTimestamp(String columnName, Calendar cal) throws SQLException {
		throw new Error("Unsupported");
	}

	public URL getURL(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public URL getURL(String columnName) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateRef(int columnIndex, Ref x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateRef(String columnName, Ref x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBlob(int columnIndex, Blob x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBlob(String columnName, Blob x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateClob(int columnIndex, Clob x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateClob(String columnName, Clob x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateArray(int columnIndex, Array x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateArray(String columnName, Array x) throws SQLException {
		throw new Error("Unsupported");
	}

	public int getHoldability() throws SQLException {
		throw new Error("Unsupported");
	}

	public Reader getNCharacterStream(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public Reader getNCharacterStream(String columnLabel) throws SQLException {
		throw new Error("Unsupported");
	}

	public NClob getNClob(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public NClob getNClob(String columnLabel) throws SQLException {
		throw new Error("Unsupported");
	}

	public String getNString(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public String getNString(String columnLabel) throws SQLException {
		throw new Error("Unsupported");
	}

	public Object getObject(int columnIndex, Map<String, Class<?>> map) throws SQLException {
		throw new Error("Unsupported");
	}

	public Object getObject(String columnLabel, Map<String, Class<?>> map) throws SQLException {
		throw new Error("Unsupported");
	}

	public RowId getRowId(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public RowId getRowId(String columnLabel) throws SQLException {
		throw new Error("Unsupported");
	}

	public SQLXML getSQLXML(int columnIndex) throws SQLException {
		throw new Error("Unsupported");
	}

	public SQLXML getSQLXML(String columnLabel) throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean isClosed() throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateAsciiStream(int columnIndex, InputStream x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateAsciiStream(String columnLabel, InputStream x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateAsciiStream(int columnIndex, InputStream x, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateAsciiStream(String columnLabel, InputStream x, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBinaryStream(int columnIndex, InputStream x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBinaryStream(String columnLabel, InputStream x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBinaryStream(int columnIndex, InputStream x, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBinaryStream(String columnLabel, InputStream x, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBlob(int columnIndex, InputStream inputStream) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBlob(String columnLabel, InputStream inputStream) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBlob(int columnIndex, InputStream inputStream, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateBlob(String columnLabel, InputStream inputStream, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateCharacterStream(int columnIndex, Reader x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateCharacterStream(String columnLabel, Reader reader) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateCharacterStream(int columnIndex, Reader x, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateCharacterStream(String columnLabel, Reader reader, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateClob(int columnIndex, Reader reader) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateClob(String columnLabel, Reader reader) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateClob(int columnIndex, Reader reader, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateClob(String columnLabel, Reader reader, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNCharacterStream(int columnIndex, Reader x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNCharacterStream(String columnLabel, Reader reader) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNCharacterStream(int columnIndex, Reader x, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNCharacterStream(String columnLabel, Reader reader, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNClob(int columnIndex, NClob clob) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNClob(String columnLabel, NClob clob) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNClob(int columnIndex, Reader reader) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNClob(String columnLabel, Reader reader) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNClob(int columnIndex, Reader reader, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNClob(String columnLabel, Reader reader, long length) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNString(int columnIndex, String string) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateNString(String columnLabel, String string) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateRowId(int columnIndex, RowId x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateRowId(String columnLabel, RowId x) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateSQLXML(int columnIndex, SQLXML xmlObject) throws SQLException {
		throw new Error("Unsupported");
	}

	public void updateSQLXML(String columnLabel, SQLXML xmlObject) throws SQLException {
		throw new Error("Unsupported");
	}

	public boolean isWrapperFor(Class<?> iface) throws SQLException {
		throw new Error("Unsupported");
	}

	public <T> T unwrap(Class<T> iface) throws SQLException {
		throw new Error("Unsupported");
	}

}