Re: Abandoning PGobject - Mailing list pgsql-jdbc

Hi,

I just attached two abstract classes that can are useful as base classes
for type drivers, and a sample implementation that serves a PGobject
implementation.

During hacking, I noticed that adding a "String sqltype" parameter to
the get* methods would help for complete type orthogonality (this way a
single Driver could handle all PGobjects, and possibly a second one all
the typeMap / SQLData issues).

Markus
/*
 * AbstractTextBinaryTypeDriver.java
 *
 * (C) 28.02.2005 Markus Schaber, Logi-Track ag, CH 8001 Zuerich
 *
 * $Id: $
 */
package org.postgresql.types;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.math.BigDecimal;
import java.net.URL;
import java.sql.Date;
import java.sql.SQLException;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.Calendar;

/** Should serve as a convenience base class for most TypeDrivers */
public abstract class AbstractTextBinaryTypeDriver extends AbstractTextTypeDriver
        implements
            TypeBinaryReader,
            TypeBinaryWriter {

    public boolean supportsBinaryWrite() {
        return true;
    }

    public boolean supportsBinaryReading() {
        return true;
    }

    // *** TypeBinaryReader methods ***
    public String getString(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public boolean getBoolean(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public byte getByte(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public short getShort(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public int getInt(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public long getLong(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public float getFloat(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public double getDouble(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public BigDecimal getBigDecimal(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public byte[] getBytes(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Date getDate(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Date getDate(byte[] data, int start, int length, Calendar cal) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Time getTime(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Time getTime(byte[] data, int start, int length, Calendar cal) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Timestamp getTimestamp(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Timestamp getTimestamp(byte[] data, int start, int length, Calendar cal)
            throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public InputStream getAsciiStream(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public InputStream getUnicodeStream(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public InputStream getBinaryStream(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Object getObject(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Reader getCharacterStream(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public URL getURL(byte[] data, int start, int length) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    // *** TypeBinaryWriter Methods ***
    public abstract int objectBytesLength(Object data) throws SQLException;

    public abstract void renderObject(Object data, byte[] target, int startindex);

    public void renderObject(Object data, OutputStream outstream) throws SQLException, IOException {
        byte[] temp = new byte[objectBytesLength(data)];
        renderObject(data, temp, 0);
        outstream.write(temp);
    }
}
/*
 * AbstractTextBinaryTypeDriver.java
 *
 * (C) 28.02.2005 Markus Schaber, Logi-Track ag, CH 8001 Zuerich
 *
 * $Id: $
 */
package org.postgresql.types;

import org.postgresql.PGConnection;

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.io.Writer;
import java.math.BigDecimal;
import java.net.URL;
import java.sql.Date;
import java.sql.SQLException;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.Calendar;

/** Should serve as a convenience base class for most TypeDrivers */
public abstract class AbstractTextTypeDriver implements TypeTextReader, TypeTextWriter, TypeDriver {
    public static final Class[] EMPTY_CLASSES = new Class[0];
    public static final String[] EMPTY_TYPES = new String[0];

    protected Class[] supportedClasses = EMPTY_CLASSES;
    protected String[] supportedTypes = EMPTY_TYPES;

    // *** TypeDriver methods ***
    public Class[] getSupportedClasses() {
        return supportedClasses;
    }

    public String[] getSupportedTypes() {
        return supportedTypes;
    }

    public boolean supports(String type) {
        for (int i = 0; i < supportedTypes.length; i++) {
            if (supportedTypes[i].equals(type)) {
                return true;
            }
        }
        return false;
    }

    public boolean supports(Class klass) {
        for (int i = 0; i < supportedClasses.length; i++) {
            if (supportedClasses[i].isAssignableFrom(klass)) {
                return true;
            }
        }
        return false;
    }

    public abstract String sqlType(Object data) throws SQLException;

    public boolean supportsBinaryWrite() {
        return false;
    }

    public boolean supportsTextWrite() {
        return true;
    }

    public boolean supportsBinaryReading() {
        return false;
    }

    public boolean supportsTextReading() {
        return true;
    }

    public TypeDriver forConnection(PGConnection conn) {
        return this;
    }

    // *** TypeTextReader Methods

    public String getString(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public boolean getBoolean(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public byte getByte(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public short getShort(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public int getInt(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public long getLong(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public float getFloat(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public double getDouble(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public BigDecimal getBigDecimal(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public byte[] getBytes(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Date getDate(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Date getDate(String data, Calendar cal) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Time getTime(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Time getTime(String data, Calendar cal) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Timestamp getTimestamp(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Timestamp getTimestamp(String data, Calendar cal) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public InputStream getAsciiStream(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public InputStream getUnicodeStream(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public InputStream getBinaryStream(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Object getObject(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public Reader getCharacterStream(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    public URL getURL(String data) throws SQLException {
        throw new SQLException("Unknown type!");
    }

    // *** TypeTextWriter Methods ***
    public abstract int objectCharLength(Object data) throws SQLException;

    public abstract String renderObject(Object data);

    public void renderObject(Object data, StringBuffer sb) {
        sb.append(renderObject(data));
    }

    public void renderObject(Object data, char[] target, int startindex) {
        String rep = renderObject(data);
        for (int i = 0; i < rep.length(); i++) {
            target[i + startindex] = rep.charAt(i);
        }
    }

    public void renderObject(Object data, Writer target) throws IOException {
        target.write(renderObject(data));
    }
}
/*
 * PGobjectHandler.java
 *
 * (C) 28.02.2005 Markus Schaber, Logi-Track ag, CH 8001 Zuerich
 *
 * $Id: $
 */
package org.postgresql.types;

import org.postgresql.util.PGobject;

import java.io.IOException;
import java.io.Writer;
import java.sql.SQLException;

public class PGobjectHandler extends AbstractTextTypeDriver {

    public PGobjectHandler(String sqltype, Class klass) {
        this.supportedClasses = new Class[]{klass};
        this.supportedTypes = new String[]{sqltype};
    }

    public String sqlType(Object data) throws SQLException {
        PGobject po = (PGobject) data;
        return po.getType();
    }

    public int objectCharLength(Object data) throws SQLException {
        PGobject po = (PGobject) data;
        return po.getValue().length();
    }

    public String renderObject(Object data) {
        PGobject po = (PGobject) data;
        return po.getValue();
    }

    public String getString(String data) throws SQLException {
        return data;
    }

    public Object getObject(String data) throws SQLException {
        PGobject po;
        try {
            po = (PGobject) supportedClasses[0].newInstance();
        } catch (InstantiationException e) {
            throw new SQLException("Cannot create PGObject instance " + e.getMessage());
        } catch (IllegalAccessException e) {
            throw new SQLException("Cannot create PGObject instance " + e.getMessage());
        }
        po.setValue(data);
        return po;
    }

    public void renderObject(Object data, StringBuffer sb) {
        sb.append(renderObject(data));
    }

    public void renderObject(Object data, char[] target, int startindex) {
        String rep = renderObject(data);
        for (int i = 0; i < rep.length(); i++) {
            target[i + startindex] = rep.charAt(i);
        }
    }

    public void renderObject(Object data, Writer target) throws IOException {
        target.write(renderObject(data));
    }
}