Attached are a patch to allow the charset encoding used by the JDBC

driver to be set, and a description of said patch.  Please refer to
the latter for more information.

William
--
William Webber                               william@peopleweb.net.au

src/interfaces/jdbc/org/postgresql/Connection.java

@@ -10,7 +10,7 @@ import org.postgresql.largeobject.*;
 import org.postgresql.util.*;
 
 /**
- * $Id: Connection.java,v 1.4 2000/06/06 11:05:59 peter Exp $
+ * $Id: Connection.java,v 1.5 2000/09/12 04:58:47 momjian Exp $
  *
  * This abstract class is used by org.postgresql.Driver to open either the JDBC1 or
  * JDBC2 versions of the Connection class.
@@ -30,6 +30,14 @@ public abstract class Connection
   private String PG_PASSWORD;
   private String PG_DATABASE;
   private boolean PG_STATUS;
+
+  /**
+   *  The encoding to use for this connection.
+   *  If <b>null</b>, the encoding has not been specified by the
+   *  user, and the default encoding for the platform should be
+   *  used.
+   */
+  private String encoding;
   
   public boolean CONNECTION_OK = true;
   public boolean CONNECTION_BAD = false;
@@ -111,6 +119,8 @@ public abstract class Connection
     PG_PORT = port;
     PG_HOST = new String(host);
     PG_STATUS = CONNECTION_BAD;
+
+    encoding = info.getProperty("charSet");  // could be null
     
     // Now make the initial connection
     try
@@ -154,7 +164,8 @@ public abstract class Connection
 		// The most common one to be thrown here is:
 		// "User authentication failed"
 		//
-		throw new SQLException(pg_stream.ReceiveString(4096));
+		throw new SQLException(pg_stream.ReceiveString
+                                       (4096, getEncoding()));
 		
 	      case 'R':
 		// Get the type of request
@@ -224,7 +235,8 @@ public abstract class Connection
           break;
 	case 'E':
 	case 'N':
-           throw new SQLException(pg_stream.ReceiveString(4096));
+           throw new SQLException(pg_stream.ReceiveString
+                                  (4096, getEncoding()));
         default:
           throw new PSQLException("postgresql.con.setup");
       }
@@ -313,7 +325,7 @@ public abstract class Connection
 	    
 	    Field[] fields = null;
 	    Vector tuples = new Vector();
-	    byte[] buf = new byte[sql.length()];
+	    byte[] buf = null;
 	    int fqp = 0;
 	    boolean hfr = false;
 	    String recv_status = null, msg;
@@ -325,6 +337,18 @@ public abstract class Connection
 	    // larger than 8K. Peter June 6 2000
 	    //if (sql.length() > 8192)
 	    //throw new PSQLException("postgresql.con.toolong",sql);
+
+        if (getEncoding() == null)
+            buf = sql.getBytes();
+        else {
+            try {
+                buf = sql.getBytes(getEncoding());
+            } catch (UnsupportedEncodingException unse) {
+                 throw new PSQLException("postgresql.con.encoding",
+                                        unse);
+            }
+        }
+
 	    try
 		{
 		    pg_stream.SendChar('Q');
@@ -513,6 +537,15 @@ public abstract class Connection
     {
 	return PG_USER;
     }
+
+    /**
+     *  Get the character encoding to use for this connection.
+     *  @return the encoding to use, or <b>null</b> for the 
+     *  default encoding.
+     */
+    public String getEncoding() throws SQLException {
+        return encoding;
+    }
     
     /**
      * This returns the Fastpath API for the current connection.

src/interfaces/jdbc/org/postgresql/Driver.java

@@ -90,7 +90,15 @@ public class Driver implements java.sql.Driver
    * <p>The java.util.Properties argument can be used to pass arbitrary
    * string tag/value pairs as connection arguments.  Normally, at least
    * "user" and "password" properties should be included in the 
-   * properties.
+   * properties.  In addition, the "charSet" property can be used to 
+   * set a character set encoding (e.g. "utf-8") other than the platform 
+   * default (typically Latin1).  This is necessary in particular if storing 
+   * multibyte characters in the database.  For a list of supported
+   * character encoding , see 
+   * http://java.sun.com/products/jdk/1.2/docs/guide/internat/encoding.doc.html
+   * Note that you will probably want to have set up the Postgres database
+   * itself to use the same encoding, with the "-E <encoding>" argument
+   * to createdb.
    *
    * Our protocol takes the forms:
    * <PRE>

src/interfaces/jdbc/org/postgresql/PG_Stream.java

@@ -235,17 +235,22 @@ public class PG_Stream
       }
       return n;
   }
+
+    public String ReceiveString(int maxsize) throws SQLException {
+        return ReceiveString(maxsize, null);
+    }
   
   /**
    * Receives a null-terminated string from the backend.  Maximum of
    * maxsiz bytes - if we don't see a null, then we assume something
    * has gone wrong.
    *
-   * @param maxsiz maximum length of string
+   * @param encoding the charset encoding to use.
+   * @param maxsiz maximum length of string in bytes
    * @return string from back end
    * @exception SQLException if an I/O error occurs
    */
-  public String ReceiveString(int maxsiz) throws SQLException
+  public String ReceiveString(int maxsiz, String encoding) throws SQLException
   {
     byte[] rst = new byte[maxsiz];
     int s = 0;
@@ -267,7 +272,16 @@ public class PG_Stream
       } catch (IOException e) {
 	throw new PSQLException("postgresql.stream.ioerror",e);
       }
-      String v = new String(rst, 0, s);
+      String v = null;
+      if (encoding == null)
+          v = new String(rst, 0, s);
+      else {
+          try {
+              v = new String(rst, 0, s, encoding);
+          } catch (UnsupportedEncodingException unse) {
+              throw new PSQLException("postgresql.stream.encoding", unse);
+          }
+      }
       return v;
   }
   

src/interfaces/jdbc/org/postgresql/jdbc1/ResultSet.java

@@ -163,7 +163,16 @@ public class ResultSet extends org.postgresql.ResultSet implements java.sql.Resu
     wasNullFlag = (this_row[columnIndex - 1] == null);
     if(wasNullFlag)
       return null;
-    return new String(this_row[columnIndex - 1]);
+    String encoding = connection.getEncoding();
+    if (encoding == null)
+        return new String(this_row[columnIndex - 1]);
+    else {
+        try {
+            return new String(this_row[columnIndex - 1], encoding);
+        } catch (UnsupportedEncodingException unse) {
+            throw new PSQLException("postgresql.res.encoding", unse);
+        }
+    }
   }
   
   /**

src/interfaces/jdbc/org/postgresql/jdbc2/ResultSet.java

@@ -164,7 +164,16 @@ public class ResultSet extends org.postgresql.ResultSet implements java.sql.Resu
     wasNullFlag = (this_row[columnIndex - 1] == null);
     if(wasNullFlag)
       return null;
-    return new String(this_row[columnIndex - 1]);
+    String encoding = connection.getEncoding();
+    if (encoding == null)
+        return new String(this_row[columnIndex - 1]);
+    else {
+        try {
+            return new String(this_row[columnIndex - 1], encoding);
+        } catch (UnsupportedEncodingException unse) {
+            throw new PSQLException("postgresql.res.encoding", unse);
+        }
+    }
   }
   
   /**