ImageTransfer.java Source code

Introduction

Here is the source code for ImageTransfer.java

Source

/**
 * Transfer type to transfer SWT ImageData objects.
 */

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;

import org.eclipse.swt.SWT;
import org.eclipse.swt.dnd.ByteArrayTransfer;
import org.eclipse.swt.dnd.DND;
import org.eclipse.swt.dnd.TransferData;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.ImageLoader;

public class ImageTransfer extends ByteArrayTransfer {

    private static final String TYPENAME = "imagedata";

    private static final int TYPEID = registerType(TYPENAME);

    private static ImageTransfer _instance = new ImageTransfer();

    public static ImageTransfer getInstance() {
        return _instance;
    }

    public void javaToNative(Object object, TransferData transferData) {
        if (!checkImage(object) || !isSupportedType(transferData)) {
            DND.error(DND.ERROR_INVALID_DATA);
        }
        ImageData imdata = (ImageData) object;
        try {
            // write data to a byte array and then ask super to convert to
            // pMedium
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            DataOutputStream writeOut = new DataOutputStream(out);
            ImageLoader loader = new ImageLoader();
            loader.data = new ImageData[] { imdata };
            loader.save(writeOut, SWT.IMAGE_BMP);
            writeOut.close();
            byte[] buffer = out.toByteArray();
            super.javaToNative(buffer, transferData);
            out.close();
        } catch (IOException e) {
        }
    }

    public Object nativeToJava(TransferData transferData) {
        if (!isSupportedType(transferData))
            return null;

        byte[] buffer = (byte[]) super.nativeToJava(transferData);
        if (buffer == null)
            return null;

        ImageData imdata;
        try {
            ByteArrayInputStream in = new ByteArrayInputStream(buffer);
            DataInputStream readIn = new DataInputStream(in);
            imdata = new ImageData(readIn);
            readIn.close();
        } catch (IOException ex) {
            return null;
        }
        return imdata;
    }

    protected String[] getTypeNames() {
        return new String[] { TYPENAME };
    }

    protected int[] getTypeIds() {
        return new int[] { TYPEID };
    }

    boolean checkImage(Object object) {
        return (object != null && object instanceof ImageData);
    }

    protected boolean validate(Object object) {
        return checkImage(object);
    }
}