Oracle 9i +Java: Change string encoding from UTF-16 to Windows-1251

Question

Dear colleagues,
I have a very urgent case: need to change encoding of the string retrieved from the file (with encoding UTF-16) to Windows-1251 and put it to db table, to CLOB field.
Code of the Java function
+public static void file2table(String sql, String fileName, String characterSet, int asByteArray) throws SQLException, IOException {+
Connection con = null;
Writer writer = null;
Reader reader = null;
+try {+
con = getConnection();
PreparedStatement ps=con.prepareStatement(sql);
reader = new InputStreamReader(new BufferedInputStream(new FileInputStream(new File(fileName))), characterSet);
BufferedReader br = new BufferedReader(reader);
String s;
+while ((s = br.readLine()) != null) {+
byte[] defaultBytes=s.getBytes(characterSet);
String win1251str=new String(defaultBytes, "windows-1251");
+if(asByteArray>0) {+
ps.setBytes(1, defaultBytes);
+//ps.setBytes(1, win1251str.getBytes("windows-1251"));+
+} else {+
ps.setString(1, s);
+}+
ps.executeUpdate();
+}+
con.commit();
+} finally {+
+if (reader != null) {reader.close();}+
+if (con != null) {con.close();}+
+}+
+}+
I was check, all bytes from the file received correctly. But if I put readed bytes to database table, result text in table is broken.

Answer 1

>
Yes, currently I already have filled table with all file lines in result table but with incorrect encoding
>
No you haven't - not using the code you posted. You can't save LOB data using only the BLOB or CLOB.
That isn't data that you strored - it is garbage that is being stored as the LOB locator.
I ask you why you were trying to store the data that way instead of the way the doc shows you and you said
>
Because var. s is type of Java String.
For method setClob must be use type of CLOB
>
You are teriibly confused about LOBs. A BLOB or CLOB Java datatype is the LOB LOCATOR and doesn't contain any data.
Yes - it is true that method setClob must be of type CLOB but that CLOB instance HAS TO BE THE LOB LOCATOR - not the data.
You access LOB data using streams. To store LOB data you have to RETRIEVE (not send) a LOB locator from the database and then use the locator's stream to send the actual data.
So if you are creating a new record in the table you typically do an INSERT that includes an EMPTY_LOB() and have the newly created LOB locator returned to you. Then you use that locators stream to send the actual data.
Since you are not doing that your approach will not work.
Here is a link to the 9i JDBC Dev Guide
http://docs.oracle.com/cd/B10501_01/java.920/a96654.pdf
See page 8-2 to start with
>
BLOB and CLOB data is
accessed and referenced by using a locator, which is stored in the database table and
points to the BLOB or CLOB data, which is outside the table.
To work with LOB data, you must first obtain a LOB locator. Then you can read or
write LOB data and perform data manipulation. The following sections also
describe how to create and populate a LOB column in a table.
The oracle.sql.BLOB and CLOB classes implement the java.sql.Blob and
Clob interfaces, respectively (oracle.jdbc2.Blob and Clob interfaces under
JDK 1.1.x). By contrast, BFILE is an Oracle extension, without a corresponding
java.sql (or oracle.jdbc2) interface.
Instances of these classes contain only the locators for these datatypes, not the data.
After accessing the locators, you must perform some additional steps to access the
data. These steps are described in "Reading and Writing BLOB and CLOB Data" on
page 8-6 and "Reading BFILE Data" on page 8-22.
Note: You cannot construct BLOB, CLOB, or BFILE objects in your
JDBC application—you can only retrieve existing BLOBs, CLOBs,
or BFILEs from the database or create them using the
createTemporary() and empty_lob() methods.
>
Read the above quotes several times until you understand what they are telling you. These are the two main concepts you need to accept:
>
To work with LOB data, you must first obtain a LOB locator.
You cannot construct BLOB, CLOB, or BFILE objects in your JDBC application
>
See the example code and description starting on page 8-11 for how to populate a LOB column in a table
>
Create a BLOB or CLOB column in a table with the SQL CREATE TABLE statement,
then populate the LOB. This includes creating the LOB entry in the table, obtaining
the LOB locator, creating a file handler for the data (if you are reading the data from
a file), and then copying the data into the LOB.
>
Until you start using the proper methodology you are just wasting you time and will not be successful.