import  oracle.jdbc.OracleTypes;
 import  oracle.sql.CLOB;

 import  java.sql.*;

 public   class  ClobTest {

   private   static   final  String USERNAME = "<username>";

   private   static   final  String PASSWORD = "<password>";

   private   static   final  String SERVER = "jdbc:oracle:thin:@<host>:<port>:<SERVICE_NAME>";

   private   static   final  String RESOURCE = "ЙЦУКЕНйцукенQWERTYqwerty";

   public   static   void  main(String args [])
     throws  Exception {
    Connection con =  null ;
    Statement st =  null ;
    CallableStatement cst =  null ;
    ResultSet rs =  null ;
     try  {
      DriverManager.registerDriver( new  oracle.jdbc.OracleDriver());
      con = DriverManager.getConnection(SERVER, USERNAME, PASSWORD);
      con.setAutoCommit(false);
      st = con.createStatement();
       try  {
        st.execute("drop table test_lob");
      }  catch  (SQLException e) {}
      st.execute("create table test_lob (test_lob_id number(9), cdata clob)");
      
      // Первый способ
      CLOB clob = CLOB.createTemporary(con, true, CLOB.DURATION_SESSION);
      clob.putChars( 1 , RESOURCE.toCharArray());
      cst = con.prepareCall("insert into test_lob (test_lob_id, cdata) values (1, ?)");
      cst.setClob( 1 , clob);
      cst.execute();
      // Второй способ
      cst = con.prepareCall(
        "begin\n" +
        "  insert into test_lob (test_lob_id, cdata)\n" +
        "  values (2, empty_clob())\n" +
        "  return cdata into ?;\n" +
        "end;"
      );
      cst.registerOutParameter( 1 , OracleTypes.CLOB);
      cst.execute();
      clob = (CLOB) cst.getClob( 1 );
      clob.putChars( 1 , RESOURCE.toCharArray());
      cst = con.prepareCall("update test_lob set cdata = ? where test_lob_id = 2");
      cst.setClob( 1 , clob);
      cst.execute();
      // Проверка
      rs = st.executeQuery("select test_lob_id, cdata from test_lob");
       while  (rs.next()) {
        clob = (CLOB) rs.getClob("cdata");
        System.out.println(
          rs.getInt("test_lob_id") + " " + clob.getSubString( 1 , ( int )clob.getLength())
        );
      }
    }  finally  {
       if  (rs !=  null ) { rs.close(); }
       if  (cst !=  null ) { cst.close(); }
       if  (st !=  null ) { st.close(); }
       if  (con !=  null ) { con.close(); }
    }
  }
}

File inXML= new  File("d:\\Dima\\oa_meteor_Planeta.xml");
InputStream inX= new  FileInputStream(inXML);
inX.read(buf); int  i= 0 ;cmd="";
 while  (buf[i]!= 0 ){cmd+=( char )buf[i];i++};
System.out.println("XML-document:\n"+cmd);cmd= null ;

String outs=clob.getSubString( 1 ,( int )clob.getChunkSize());
cmd= new  String(outs.getBytes(),"utf-8");
System.out.println("The field clob contains\n"+clob.getChunkSize()+"\n"+cmd);

 import  oracle.sql.CLOB;

 import  java.io.*;
 import  java.sql.*;

 public   class  ClobTest {

   private   static   final  String USERNAME = "<username>";

   private   static   final  String PASSWORD = "<password>";

   private   static   final  String SERVER = "jdbc:oracle:thin:@<host>:<port>:<SERVICE_NAME>";

   public   static   void  main(String args [])
     throws  Exception {
    Connection con =  null ;
    Statement st =  null ;
    CallableStatement cst =  null ;
     try  {
      DriverManager.registerDriver( new  oracle.jdbc.OracleDriver());
      con = DriverManager.getConnection(SERVER, USERNAME, PASSWORD);
      con.setAutoCommit(false);
      st = con.createStatement();
       try  {
        st.execute("drop table test_lob");
      }  catch  (SQLException e) {}
      st.execute("create table test_lob (test_lob_id number(9), cdata clob)");
      CLOB clob = file2clob(con, "C:/Tmp/oa_meteor_planeta.xml", "Cp1251");
      cst = con.prepareCall("insert into test_lob (test_lob_id, cdata) values (1, ?)");
      cst.setClob( 1 , clob);
      cst.execute();
      con.commit();
    }  finally  {
       if  (cst !=  null ) { cst.close(); }
       if  (st !=  null ) { st.close(); }
       if  (con !=  null ) { con.close(); }
    }
  }

   public   static  CLOB file2clob(Connection con, String fileName, String characterSet)
     throws  SQLException, IOException {
    CLOB clob =  null ;
    Writer writer =  null ;
    InputStreamReader reader =  null ;
     try  {
      clob = CLOB.createTemporary(con, true, CLOB.DURATION_SESSION);
      writer = clob.getCharacterOutputStream();
      reader =  new  InputStreamReader(
         new  BufferedInputStream( new  FileInputStream( new  File(fileName))), characterSet
      );
       char [] chars =  new   char [clob.getChunkSize()];
       int  iChar;
       while  ((iChar = reader.read(chars)) != - 1 ) {
        writer.write(chars,  0 , iChar);
      }
    }  finally  {
       if  (reader !=  null ) {reader.close();}
       if  (writer !=  null ) {writer.close();}
    }
     return  clob;
  }

}

   public   void  printClob(CLOB clob, String characterSet)
     throws  SQLException, IOException {
    OutputStreamWriter writer =  null ;
    BufferedReader reader =  null ;
     try  {
      writer =  new  OutputStreamWriter( new  BufferedOutputStream(System.out), characterSet);
      reader =  new  BufferedReader(clob.getCharacterStream());
       int  length;
       char [] buf =  new   char [clob.getChunkSize()];
       while  ((length = reader.read(buf,  0 , clob.getChunkSize())) != - 1 ) {
        writer.write(buf,  0 , length);
      }
    }  finally  {
       if  (writer !=  null ) {writer.close();}
       if  (reader !=  null ) {reader.close();}
    }
  }

printClob(clob, "Cp1251");

num=stmt.executeUpdate("insert into worker(id,xdoc) values(10,sys.XMLType.CreateXML('"+cmd+"'))");

PreparedStatement pst = con.prepareStatement("insert into worker(id, xdoc) values(10, XMLType(?)";);
pst.setClob( 1 , clob);
pst.executeUpdate();

<я>яяя</я>

 try  {
  st.execute("drop table test_xml");
}  catch  (SQLException e) {}
st.execute("create table test_xml (test_xml_id number(9), xml XMLType)");
CLOB clob = file2clob(con, "C:/Tmp/test.xml", "Cp1251");
cst = con.prepareCall("insert into test_xml (test_xml_id, xml) values (1, XMLType(?))"); 

 while  ((len=oreader.read(cbuf))!=- 1 ) {
  System.out.println(cbuf);
}