| package org.eclipse.swt.dnd;
|
|
|
| /*
|
| * Copyright (c) 2000, 2002 IBM Corp. All rights reserved. |
| * This file is made available under the terms of the Common Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-v10.html
|
| */
|
|
|
| /**
|
| * <code>Transfer</code> provides a mechanism for converting between a java
|
| * representation of data and a platform specific representation of data and
|
| * vice versa. It is used in data transfer operations such as drag and drop and
|
| * clipboard copy/paste.
|
| *
|
| * <p>You should only need to become familiar with this class if you are
|
| * implementing a Transfer subclass and you are unable to subclass the
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| * ByteArrayTransfer class.</p>
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| *
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| * @see ByteArrayTransfer
|
| */ |
| public abstract class Transfer {
|
|
|
| /**
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| * Returns a list of the platform specific data types that can be converted using
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| * this transfer agent.
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| *
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| * <p>Only the data type fields of the <code>TransferData</code> objects are filled
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| * in.</p>
|
| *
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| * @return a list of the data types that can be converted using this transfer agent
|
| */ |
| abstract public TransferData[] getSupportedTypes();
|
| /**
|
| * Returns true if the <code>TransferData</code> data type can be converted
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| * using this transfer agent.
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| *
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| * @param transferData a platform specific description of a data type; only the data
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| * type fields of the <code>TransferData</code> object need to be filled in
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| *
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| * @return true if the transferData data type can be converted using this transfer
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| * agent
|
| */ |
| abstract public boolean isSupportedType(TransferData transferData);
|
|
|
| /**
|
| * Returns the platform specfic names of the data types that can be converted
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| * using this transfer agent.
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| *
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| * @return the platform specfic names of the data types that can be converted
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| * using this transfer agent.
|
| */
|
| abstract protected String[] getTypeNames();
|
|
|
| /**
|
| * Returns the platform specfic ids of the data types that can be converted using
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| * this transfer agent.
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| *
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| * @return the platform specfic ids of the data types that can be converted using
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| * this transfer agent
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| */
|
| abstract protected int[] getTypeIds();
|
|
|
| /**
|
| * Converts a java representation of data to a platform specific representation of
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| * the data.
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| *
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| * <p>On a successful conversion, the transferData.result field will be set as follows:
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| * <ul>
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| * <li>Windows: COM.S_OK
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| * <li>Motif: 1
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| * <li>GTK: 1
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| * <li>Photon: 1
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| * </ul></p>
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| *
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| * <p>If this transfer agent is unable to perform the conversion, the transferData.result
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| * field will be set to a failure value as follows:
|
| * <ul>
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| * <li>Windows: COM.DV_E_TYMED or COM.E_FAIL
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| * <li>Motif: 0
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| * <li>GTK: 0
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| * <li>Photon: 0
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| * </ul></p>
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| *
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| * @param object a java representation of the data to be converted; the type of
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| * Object that is passed in is dependant on the <code>Transfer</code> subclass.
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| *
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| * @param transferData an empty TransferData object; this object will be
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| * filled in on return with the platform specific representation of the data
|
| */
|
| abstract protected void javaToNative (Object object, TransferData transferData);
|
|
|
| /**
|
| * Converts a platform specific representation of data to a java representation.
|
| *
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| * @param transferData the platform specific representation of the data to be
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| * converted
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| *
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| * @return a java representation of the converted data if the conversion was
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| * successful; otherwise null. The type of Object that is returned is dependant
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| * on the <code>Transfer</code> subclass
|
| */
|
| abstract protected Object nativeToJava(TransferData transferData);
|
|
|
| /**
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| * Registers a name for a data type and returns the associated unique identifier.
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| *
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| * <p>You may register the same type more than once, the same unique identifier
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| * will be returned if the type has been previously registered.</p>
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| *
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| * <p>Note: On windows, do <b>not</b> call this method with pre-defined
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| * Clipboard Format types such as CF_TEXT or CF_BITMAP because the
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| * pre-defined identifier will not be returned</p>
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| *
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| * @param formatName the name of a data type
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| *
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| * @return the unique identifier associated with htis data type
|
| */ |
| public static int registerType(String formatName){
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| if (formatName == "TEXT") return 10;
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| if (formatName == "files") return 11;
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| if (formatName == "RTF") return 12;
|
| return 0;
|
| }
|
| }
|