writing methods which returns different Objects

[santhosh.R gowda]

Dear all,
I had written one function which Returns Object and takes parameter as Object also

   
public Object myfunction(Object o)
{
Object va;
if (o.toString("Integer"))
{
  val = new Integer (5);
}
if (o.toString("Boolean"))
{
  val = new Boolean(5);
}
if (o.toString("Vector"))
{
  val = new Vector();
}
if (o.toString("String"))
{
  val = new String();
}

}
 

Here the function is working fine and while calling the function i had to type cast the Value which the function returns Object
i want to alter my code such that i need not to type cast in the calling function is this possible and i had also gone through wild cars also there it suits for objects which extends Number but here im using Vectors and String also so please tell me the way to com out of this

[Campbell Ritchie]

Will that actually compile? It doesn't look at all good to me. You might do well to find the Class.forName("foo.bar.Class").newInstance() idiom. But that (I think) requires a no-arguments constructor.

[Campbell Ritchie]

Or maybe a Map<String Class><?>> which returns the Class object for a particular name?

[santhosh.R gowda]

Ya its compiled and running and currently i'm type casting the in the calling function but i want to make not to type cast for all the four objects

[Aneesh Vijendran]

Why do you want to do this?

public Object myfunction(Object o)  
{  
    return o;
}

also does the same thing.

Where ever you call any of these methods, you need to do a typecast as the signature is still Object.


Moreover:

if (o.toString("Integer"))

wont compile for sure, rather it should be

 if (o.toString().equalsIgnoreCase("Integer"))

[santhosh.R gowda]

Sorry i had used

 if (o.toString().equalsIgnoreCase("Integer"))

also does the same thing.

Where ever you call any of these methods, you need to do a typecast as the signature is still Object.

I'm using different logic based upon the Objects(Integer,Boolean,Vector ,String)

[Campbell Ritchie]

santhosh.R gowda wrote:Sorry i had used . . .

I suspected that, but we can't be sure. Please read this FAQ.

[santhosh.R gowda]

 public static  Object setPreparedStatement(String query,Object values[],Object obj,String dto) throws LMSDaoException
	{        
        AbstractDTO absDTO ;
        DTOFactory factory = new DTOFactory();
        Object rValue =null;
        try
        {
        	con  =  conn.DbConnection.getDbConnection ();
		    stmt =   con.prepareStatement(query);
		    for(int index=1;index<=values.length;index++)stmt.setObject(index,values[index-1]);

		    if(obj.toString().endsWith("Vector"))
		    {
		    	Vector  userDetailsVec  = new Vector();
		    	ds= stmt.executeQuery();
		        ResultSetMetaData rstMeta = ds.getMetaData();
		        int i =0;
		        while(ds.next())
			    {
			    	absDTO = factory.getDTOObject(dto);
			    	Map map = new HashMap();
			    	for(int j =1;j<=rstMeta.getColumnCount();j++)setDTO(map,ds.getString (rstMeta.getColumnName(j)), rstMeta.getColumnName(j));
			    	absDTO.setMap(map);				
			    	userDetailsVec.add(i++, absDTO);
			    }
			    rValue = userDetailsVec;
		    }
		    else if(obj.toString().endsWith("Integer"))rValue = new Integer(stmt.executeUpdate());    

		    else if(obj.toString().endsWith("Boolean"))rValue = new Boolean(stmt.executeQuery().next());
		    
		    else if(obj.toString().endsWith("String"))
		    {
		    	ds= stmt.executeQuery();
		    	while(ds.next())rValue=	ds.getString(1);		    	
		    }
		    
		    else if(obj.toString().endsWith("Array"))
		    {
		    	Vector  list  = new Vector();
		    	ds= stmt.executeQuery();
		    	int count=0;
		    	while(ds.next())list.add(count++,ds.getString(1));
				rValue = list;
		    }
        }
        catch(SQLException e)
        {
        	throw new LMSDaoException("Exception by SetPrepared Statement"+e.toString());
        }
        finally
		{
		    DbConnection.close(ds,stmt,con);
		    return rValue;
		}        
	}

 

Here i'm returning the Object as a return value and in my calling method i want to type cast as per my requirement