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system
I'm trying to retrieve the value of the "SHAPE" attribute of type "SDO_GEOMETRY" from a table created in an Oracle 11g Database using JDBC. However, I am unable to obtain the value of this attribute with the following code. The code works fine for retrieving other attributes from the table. Can someone please help me figure out what the issue might be?

```java
try {
    Class.forName("oracle.jdbc.driver.OracleDriver");
    System.out.println("Driver O.K.");

    String url = "jdbc:oracle:thin:@localhost:1521:xe";
    String user = "system";
    String passwd = "isima";

    Connection conn = DriverManager.getConnection(url, user, passwd);
    System.out.println("Connexion effective");

    Statement myStmt = null;
    ResultSet myRs = null;          

    myStmt = conn.createStatement();

    myRs = myStmt.executeQuery("SELECT * FROM testGeo");

    while (myRs.next()) {
        System.out.println(myRs.getString("shape"));
    } 

} catch (Exception e) {
    e.printStackTrace();
} 
```

Here are the DDL statements used to create the testGeo table and insert some test data:

```sql
CREATE TABLE testGeo (
    GeoID NUMBER PRIMARY KEY,
    name VARCHAR2(32),
    shape SDO_GEOMETRY
);

INSERT INTO testGeo VALUES(
    1,
    'cola_a',
    SDO_GEOMETRY(
        2003,
        NULL,
        NULL,
        SDO_ELEM_INFO_ARRAY(1,1003,3),
        SDO_ORDINATE_ARRAY(1,1, 5,7)
    )
);

INSERT INTO testGeo VALUES(
    2,
    'cola_b',
    SDO_GEOMETRY(
        2003,
        NULL,
        NULL,
        SDO_ELEM_INFO_ARRAY(1,1003,3),
        SDO_ORDINATE_ARRAY(2,1, 6,7)
    )
);

INSERT INTO testGeo VALUES(
    3,
    'cola_c',
    SDO_GEOMETRY(
        2003,
        NULL,
        NULL,
        SDO_ELEM_INFO_ARRAY(1,1003,3),
        SDO_ORDINATE_ARRAY(1,1, 9,9)
    )
);
```
user
The problem you are facing is due to the fact that you are trying to retrieve a complex object, which is a custom Oracle object that requires special handling with its own mapping library.

The "SHAPE" attribute of type "SDO_GEOMETRY" that you are trying to retrieve is part of the Oracle Spatial package and relies on custom objects. These objects cannot be easily read like basic SQL columns such as VARCHAR or NUMBER. That is why your call to `getString("shape")` does not return any results.

To solve this issue, you need to use the JGeometry package provided by Oracle. This package is specifically designed to handle custom Oracle objects, such as SDO_GEOMETRY.

To use the JGeometry package, you need to ensure that it is included on your classpath. Once you have it set up correctly, you can use the custom Java mappings to manipulate your shape object.

Here is an example of how you can read the geometry object from the database using JGeometry:

```java
// Reading a geometry from the database
ResultSet rs = statement.executeQuery("SELECT shape FROM testGeo");
STRUCT st = (oracle.sql.STRUCT) rs.getObject(1);
// Convert STRUCT into geometry
JGeometry j_geom = JGeometry.load(st);
```

By following this approach, you will be able to retrieve and work with the complex SDO_GEOMETRY object from your Oracle 11g Database using JDBC and the JGeometry package.
assistant