SQLUpdater.java #5

package journal.action;

import java.io.File;
import java.net.URL;
import java.net.URLClassLoader;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.SQLFeatureNotSupportedException;
import java.util.logging.Logger;

import journal.action.sql.SQLAdapter;
import journal.reader.DataJournalEntry;
import journal.reader.Options;
import journal.reader.TransactionJournalEntry;

public class SQLUpdater extends BaseAction {

	protected Connection cx;
	protected SQLAdapter sf;
	
	protected String classpath;
	protected String classname;
	protected String connectionString;

	protected void handleSQLException(SQLException ex) throws Exception {
		StringBuffer err = new StringBuffer();
		err.append( "SQLException: " + ex.getMessage() );
		err.append( " SQLState: " + ex.getSQLState() );
		err.append( " VendorError: " + ex.getErrorCode() );
		
		Exception newEx = new Exception(err.toString());
		newEx.setStackTrace(ex.getStackTrace());
		
		throw newEx;
	}
	
	final static class DriverProxy implements java.sql.Driver {
	    private final java.sql.Driver target;
	    DriverProxy(java.sql.Driver target) {
	        if (target == null) {
	            throw new NullPointerException();
	        }
	        this.target = target;
	    }
	    public java.sql.Driver getTarget() {
	        return target;
	    }
	    public boolean acceptsURL(String url) throws SQLException {
	        return target.acceptsURL(url);
	    }
	    public java.sql.Connection connect(
	        String url, java.util.Properties info
	    ) throws SQLException {
	        return target.connect(url, info);
	    }
	    public int getMajorVersion()  {
	        return target.getMajorVersion();
	    }
	    public int getMinorVersion()  {
	        return target.getMinorVersion();
	    }
	    public java.sql.DriverPropertyInfo[] getPropertyInfo(
	        String url, java.util.Properties info
	    ) throws SQLException {
	        return target.getPropertyInfo(url, info);
	    }
	    public boolean jdbcCompliant() {
	        return target.jdbcCompliant();
	    }
	    @Override
	    public String toString() {
	        return "Proxy: "+target;
	    }
	    @Override
	    public int hashCode() {
	        return target.hashCode();
	    }
	    @Override
	    public boolean equals(Object obj) {
	        if (!(obj instanceof DriverProxy)) {
	            return false;
	        }
	        DriverProxy other = (DriverProxy)obj;
	        return this.target.equals(other.target);
	    }

	    // for Java 1.7, no @Override to be compatible with 1.6
		public Logger getParentLogger() throws SQLFeatureNotSupportedException {
			// TODO Auto-generated method stub
			return null;
		}
	}

	@Override
	public void setDefaultOptions(Options options) {
		options.setOptionName(this.getClass().getName(), "classpath", "", new Options.OptionSetter()  {
			@Override
			public void set(String key, String value) {
				classpath=value;
			}
		});
		options.setOptionName(this.getClass().getName(), "classname", "", new Options.OptionSetter()  {
			@Override
			public void set(String key, String value) {
				classname=value;
			}
		});
		options.setOptionName(this.getClass().getName(), "connectionString", "", new Options.OptionSetter()  {
			@Override
			public void set(String key, String value) {
				connectionString=value;
			}
		});
	}
	
	@Override
	public void start() throws Exception {
		super.start();
		
		if (classpath == "" || classname == "" || connectionString == "") {
			String message = "No SQL parameters defined CP=" + classpath + " CN=" + classname + " CON=" + connectionString;
			throw new Exception(message);
		}
		
		File jarFile = new File(classpath);
		URL url = jarFile.toURI().toURL();
		
		ClassLoader ld = URLClassLoader.newInstance(new URL[] { url }, getClass().getClassLoader());
		
		Driver driver = (Driver) Class.forName(classname, true, ld).newInstance();
		DriverManager.registerDriver(new DriverProxy(driver));
		
		
		try {
			cx = DriverManager.getConnection(connectionString);
			
			cx.setAutoCommit(false);
			sf = new SQLAdapter(cx, options);
		}
		catch (SQLException ex) {
			handleSQLException(ex);
		}
		
		System.out.println("Connected to " + cx);
	}

	@Override
	public void finish() throws Exception {
		try {
			cx.close();
		} catch (SQLException ex) {
			handleSQLException(ex);
		}
		
		System.out.println("Disconnected from SQL Database.");
	}

	@Override
	public void commitMarker(TransactionJournalEntry entry) throws Exception {
		try {
			cx.commit();
		} catch (SQLException ex) {
			handleSQLException(ex);
		}
	}

	@Override
	public void flushMarker(TransactionJournalEntry entry) {
		// flush is ignored
	}

	@Override
	public void putValue(DataJournalEntry dataEntry) throws Exception {
		try {
			sf.putValue(dataEntry);
		} catch (SQLException ex) {
			handleSQLException(ex);
		}
	}

	@Override
	public void replaceValue(DataJournalEntry dataEntry) throws Exception {
		try {
			sf.replaceValue(dataEntry);
		} catch (SQLException ex) {
			handleSQLException(ex);
		}
	}

	@Override
	public void deleteValue(DataJournalEntry dataEntry) throws Exception {
		try {
			sf.deleteValue(dataEntry);
		} catch (SQLException ex) {
			handleSQLException(ex);
		}
	}

	@Override
	public void verifyValue(DataJournalEntry dataEntry) throws Exception {
		try {
			sf.verifyValue(dataEntry);
		} catch (SQLException ex) {
			handleSQLException(ex);
		}
	}

}