DBBlob2Array.java

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package cedar.jetweb.db;

import java.sql.Blob;
import java.sql.SQLException;
import java.util.Vector;

public abstract class DBBlob2Array{

    public static Vector<Integer> getInteger(Blob blob)
    throws SQLException{

    Vector<Integer> column = null;

    if(blob==null)return column;

    byte theBytes[] = blob.getBytes((long)1, (int)blob.length());

    column = new Vector<Integer>();

    //check that we have a multiple of 4 bytes for turning into Ints 
    //If not, discard the leftover bytes.

    int numInts = theBytes.length / 4;
    numInts *=4;
    for(int ii=0; ii< numInts; ii+=4){
        int anInt = 0;
        for(int jj=0; jj!=4; ++jj){

        int piece = (int)theBytes[ii+jj];
        
        //System.out.println(piece);

        //casting thinks it should be a signed int
        if(piece<0&&jj!=3) {
            piece+=256;
        }

        piece<<=8*jj;

        //System.out.println(piece);

        anInt+=piece;
        }
        column.add(anInt);
    }

    return(column);
    }

    public static byte[] byteMe(Vector<Integer> intArray){

    byte byteArray[] = new byte[intArray.size()*4];

    int kk=0;

    for(int ii=0; ii!= intArray.size(); ++ii){
        int anInt = intArray.get(ii);
        for(int jj=0; jj!=4; ++jj){
        byteArray[kk] = (new Integer(anInt)).byteValue();
        anInt>>=8;
        ++kk;
        }
    }

    return(byteArray);
    }

    public static byte[] byteMe(Object obj){
    return(byteMe( (Vector<Integer>)obj  ));
    }



    public static Object convert (Blob blob, Class cl)
        throws SQLException{

    if(cl.equals(Vector.class)){
        return(getInteger(blob));
    }else if (cl.equals(Blob.class)){
        return(blob);
    }else{

        System.out.println("Can only convert Blobs to vectors and blobs");
        System.out.println("you attempted to convert a blob to a "+
                   cl.getName());

        return(null);
    }
    }

}

Generated Wed Jan 17 09:14:27 GMT 2007