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Standard Widget Toolkit for GTK on aarch64
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/*******************************************************************************
* Copyright (c) 2000, 2017 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.dnd;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.gtk.*;
/**
* The class ByteArrayTransfer provides a platform specific
* mechanism for converting a java byte[] to a platform
* specific representation of the byte array and vice versa.
*
* ByteArrayTransfer is never used directly but is sub-classed
* by transfer agents that convert between data in a java format such as a
* String and a platform specific byte array.
*
*
If the data you are converting does not map to a
* byte[], you should sub-class Transfer directly
* and do your own mapping to a platform data type.
*
* The following snippet shows a subclass of ByteArrayTransfer that transfers
* data defined by the class MyType.
*
*
* public class MyType {
* public String fileName;
* public long fileLength;
* public long lastModified;
* }
*
*
*
* public class MyTypeTransfer extends ByteArrayTransfer {
*
* private static final String MYTYPENAME = "my_type_name";
* private static final int MYTYPEID = registerType(MYTYPENAME);
* private static MyTypeTransfer _instance = new MyTypeTransfer();
*
* private MyTypeTransfer() {}
*
* public static MyTypeTransfer getInstance () {
* return _instance;
* }
* public void javaToNative (Object object, TransferData transferData) {
* if (object == null || !(object instanceof MyType[])) return;
*
* if (isSupportedType(transferData)) {
* MyType[] myTypes = (MyType[]) 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);
* for (int i = 0, length = myTypes.length; i < length; i++){
* byte[] buffer = myTypes[i].fileName.getBytes();
* writeOut.writeInt(buffer.length);
* writeOut.write(buffer);
* writeOut.writeLong(myTypes[i].fileLength);
* writeOut.writeLong(myTypes[i].lastModified);
* }
* byte[] buffer = out.toByteArray();
* writeOut.close();
*
* super.javaToNative(buffer, transferData);
*
* } catch (IOException e) {
* }
* }
* }
* public Object nativeToJava(TransferData transferData){
*
* if (isSupportedType(transferData)) {
*
* byte[] buffer = (byte[])super.nativeToJava(transferData);
* if (buffer == null) return null;
*
* MyType[] myData = new MyType[0];
* try {
* ByteArrayInputStream in = new ByteArrayInputStream(buffer);
* DataInputStream readIn = new DataInputStream(in);
* while(readIn.available() > 20) {
* MyType datum = new MyType();
* int size = readIn.readInt();
* byte[] name = new byte[size];
* readIn.read(name);
* datum.fileName = new String(name);
* datum.fileLength = readIn.readLong();
* datum.lastModified = readIn.readLong();
* MyType[] newMyData = new MyType[myData.length + 1];
* System.arraycopy(myData, 0, newMyData, 0, myData.length);
* newMyData[myData.length] = datum;
* myData = newMyData;
* }
* readIn.close();
* } catch (IOException ex) {
* return null;
* }
* return myData;
* }
*
* return null;
* }
* protected String[] getTypeNames(){
* return new String[]{MYTYPENAME};
* }
* protected int[] getTypeIds(){
* return new int[] {MYTYPEID};
* }
* }
*
*
* @see Transfer
*/
public abstract class ByteArrayTransfer extends Transfer {
@Override
public TransferData[] getSupportedTypes() {
int[] types = getTypeIds();
TransferData[] data = new TransferData[types.length];
for (int i = 0; i < types.length; i++) {
data[i] = new TransferData();
data[i].type = types[i];
}
return data;
}
@Override
public boolean isSupportedType(TransferData transferData){
if (transferData == null) return false;
int[] types = getTypeIds();
for (int i = 0; i < types.length; i++) {
if (transferData.type == types[i]) return true;
}
return false;
}
/**
* This implementation of javaToNative converts a java
* byte[] to a platform specific representation.
*
* @param object a java byte[] containing the data to be converted
* @param transferData an empty TransferData object that will
* be filled in on return with the platform specific format of the data
*
* @see Transfer#nativeToJava
*/
@Override
protected void javaToNative (Object object, TransferData transferData) {
transferData.result = 0;
if (!checkByteArray(object) || !isSupportedType(transferData)) {
DND.error(DND.ERROR_INVALID_DATA);
}
byte[] buffer = (byte[])object;
if (buffer.length == 0) return;
long pValue = OS.g_malloc(buffer.length);
if (pValue == 0) return;
C.memmove(pValue, buffer, buffer.length);
transferData.length = buffer.length;
transferData.format = 8;
transferData.pValue = pValue;
transferData.result = 1;
}
/**
* This implementation of nativeToJava converts a platform specific
* representation of a byte array to a java byte[].
*
* @param transferData the platform specific representation of the data to be converted
* @return a java byte[] containing the converted data if the conversion was
* successful; otherwise null
*
* @see Transfer#javaToNative
*/
@Override
protected Object nativeToJava(TransferData transferData) {
if ( !isSupportedType(transferData) || transferData.pValue == 0) return null;
int size = transferData.format * transferData.length / 8;
if (size == 0) return null;
byte[] buffer = new byte[size];
C.memmove(buffer, transferData.pValue, size);
return buffer;
}
boolean checkByteArray(Object object) {
return (object instanceof byte[] && ((byte[])object).length > 0);
}
}