how to Retrive the CLOB value from Oracle using java

Question

SELECT DESCRIPTION,DETAILED_DESCRIPTION,PRIORITY,RISK_LEVE FROM Table_Name

The DETAILED_DESCRIPTION column is having value in CLOB

Below is the code is used to fetch the data: But i am getting the error "Error: Read error" while reading the field "DETAILED_DESCRIPTION"

Statement statement;

ResultSet resultSet;

oracleCon.setAutoCommit(false);

statement = oracleCon.createStatement();

String chdet[] = new String[8];
String query="SELECT DESCRIPTION,DETAILED_DESCRIPTION,PRIORITY,RISK_LEVEL FROM Table_Name"; 

                    resultSet = statement.executeQuery(query);
                    ArrayList<String> record=new ArrayList<String>();               

                    while (resultSet.next())
                    {
                    record.add(resultSet.getString("DESCRIPTION"));                 
                    record.add(resultSet.getString("DETAILED_DESCRIPTION"));
                    record.add(resultSet.getString("PRIORITY"));
                    record.add(resultSet.getString("RISK_LEVEL"));              
                    }                   
                    if(record.size()>0)             
                    {
                        chdet[0] = record.get(0);
                        chdet[1] = record.get(1);
                        chdet[2] = record.get(2);
                        chdet[3] = record.get(3);
                        break;                          
                    }                               
                }
            return chdet;   

Answer 1

After retrieving your data, you can use the getClob () method to return your Clob. Then you needs to open the Clob's stream to read the data (Mayb be char or binary data).

If the clob is known to be a plain string, you maybe also wish to use

clob.getSubString(1, (int) clob.length());

So try this

Clob clob = resultSet.getClob("DETAILED_DESCRIPTION")
record.add(clob.getSubString(1, (int) clob.length());

see http://www.java2s.com/Code/JavaAPI/java.sql/ResultSetgetClobintcolumnIndex.htm

Answer 2

This might help you,

    // Select LOB locator into standard result set.
ResultSet rs =
   stmt.executeQuery ("SELECT blob_col, clob_col FROM lob_table");
while (rs.next())
{
   // Get LOB locators into Java wrapper classes.
   java.sql.Blob blob = rs.getBlob(1);
   java.sql.Clob clob = rs.getClob(2);

}

Refer to below link for more details, http://docs.oracle.com/cd/A84870_01/doc/java.816/a81354/oralob2.htm