Java example source code file (CImage.m)

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Java - Java tags/keywords

cfretain, cimage_createimagerep, jnf_cocoa_enter, jnf_cocoa_exit, jni_abort, jnicall, jnienv, jniexport, nsbitmapimagerep, nsgraphicscontext, nsimage, nsstring, null

The CImage.m Java example source code

/*
 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

#import <Cocoa/Cocoa.h>
#import <JavaNativeFoundation/JavaNativeFoundation.h>

#import "GeomUtilities.h"
#import "ThreadUtilities.h"

#import "sun_lwawt_macosx_CImage.h"


static void CImage_CopyArrayIntoNSImageRep
(jint *srcPixels, jint *dstPixels, int width, int height)
{
    int x, y;
    // TODO: test this on big endian systems (not sure if its correct)...
    for (y = 0; y < height; y++) {
        for (x = 0; x < width; x++) {
            jint pix = srcPixels[x];
            jint a = (pix >> 24) & 0xff;
            jint r = (pix >> 16) & 0xff;
            jint g = (pix >>  8) & 0xff;
            jint b = (pix      ) & 0xff;
            dstPixels[x] = (b << 24) | (g << 16) | (r << 8) | a;
        }
        srcPixels += width; // TODO: use explicit scanStride
        dstPixels += width;
    }
}

static void CImage_CopyNSImageIntoArray
(NSImage *srcImage, jint *dstPixels, int width, int height)
{
    CGColorSpaceRef colorspace = CGColorSpaceCreateDeviceRGB();
    CGContextRef cgRef = CGBitmapContextCreate(dstPixels, width, height, 8, width * 4, colorspace, kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host);
    CGColorSpaceRelease(colorspace);
    NSGraphicsContext *context = [NSGraphicsContext graphicsContextWithGraphicsPort:cgRef flipped:NO];
    CGContextRelease(cgRef);
    NSGraphicsContext *oldContext = [[NSGraphicsContext currentContext] retain];
    [NSGraphicsContext setCurrentContext:context];
    NSRect rect = NSMakeRect(0, 0, width, height);
    [srcImage drawInRect:rect
                fromRect:rect
               operation:NSCompositeSourceOver
                fraction:1.0];
    [NSGraphicsContext setCurrentContext:oldContext];
    [oldContext release];
}

static NSBitmapImageRep* CImage_CreateImageRep(JNIEnv *env, jintArray buffer, jint width, jint height)
{
    NSBitmapImageRep* imageRep = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL
                                                                         pixelsWide:width
                                                                         pixelsHigh:height
                                                                      bitsPerSample:8
                                                                    samplesPerPixel:4
                                                                           hasAlpha:YES
                                                                           isPlanar:NO
                                                                     colorSpaceName:NSDeviceRGBColorSpace
                                                                       bitmapFormat:NSAlphaFirstBitmapFormat
                                                                        bytesPerRow:width*4 // TODO: use explicit scanStride
                                                                       bitsPerPixel:32];

    jint *imgData = (jint *)[imageRep bitmapData];
    if (imgData == NULL) return 0L;

    jint *src = (*env)->GetPrimitiveArrayCritical(env, buffer, NULL);
    if (src == NULL) return 0L;

    CImage_CopyArrayIntoNSImageRep(src, imgData, width, height);

    (*env)->ReleasePrimitiveArrayCritical(env, buffer, src, JNI_ABORT);

    return imageRep;
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeCreateNSImageFromArray
 * Signature: ([III)J
 */
JNIEXPORT jlong JNICALL Java_sun_lwawt_macosx_CImage_nativeCreateNSImageFromArray
(JNIEnv *env, jclass klass, jintArray buffer, jint width, jint height)
{
    jlong result = 0L;

JNF_COCOA_ENTER(env);

    NSBitmapImageRep* imageRep = CImage_CreateImageRep(env, buffer, width, height);
    if (imageRep) {
        NSImage *nsImage = [[NSImage alloc] initWithSize:NSMakeSize(width, height)];
        [nsImage addRepresentation:imageRep];
        [imageRep release];

        if (nsImage != nil) {
            CFRetain(nsImage); // GC
        }

        result = ptr_to_jlong(nsImage);
    }

JNF_COCOA_EXIT(env);

    return result;
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeCreateNSImageFromArrays
 * Signature: ([[I[I[I)J
 */
JNIEXPORT jlong JNICALL Java_sun_lwawt_macosx_CImage_nativeCreateNSImageFromArrays
(JNIEnv *env, jclass klass, jobjectArray buffers, jintArray widths, jintArray heights)
{
    jlong result = 0L;

JNF_COCOA_ENTER(env);

    jsize num = (*env)->GetArrayLength(env, buffers);
    NSMutableArray * reps = [NSMutableArray arrayWithCapacity: num];

    jint * ws = (*env)->GetIntArrayElements(env, widths, NULL);
    jint * hs = (*env)->GetIntArrayElements(env, heights, NULL);

    jsize i;
    for (i = 0; i < num; i++) {
        jintArray buffer = (*env)->GetObjectArrayElement(env, buffers, i);

        NSBitmapImageRep* imageRep = CImage_CreateImageRep(env, buffer, ws[i], hs[i]);
        if (imageRep) {
            [reps addObject: imageRep];
        }
    }

    (*env)->ReleaseIntArrayElements(env, heights, hs, JNI_ABORT);
    (*env)->ReleaseIntArrayElements(env, widths, ws, JNI_ABORT);

    if ([reps count]) {
        NSImage *nsImage = [[NSImage alloc] initWithSize:NSMakeSize(0, 0)];
        [nsImage addRepresentations: reps];

        if (nsImage != nil) {
            CFRetain(nsImage); // GC
        }

        result = ptr_to_jlong(nsImage);
    }

JNF_COCOA_EXIT(env);

    return result;
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeCreateNSImageFromIconSelector
 * Signature: (I)J
 */
JNIEXPORT jlong JNICALL Java_sun_lwawt_macosx_CImage_nativeCreateNSImageFromIconSelector
(JNIEnv *env, jclass klass, jint selector)
{
    NSImage *image = nil;

JNF_COCOA_ENTER(env);

    IconRef iconRef;
    if (noErr == GetIconRef(kOnSystemDisk, kSystemIconsCreator, selector, &iconRef)) {
        image = [[NSImage alloc] initWithIconRef:iconRef];
        if (image) CFRetain(image); // GC
        ReleaseIconRef(iconRef);
    }

JNF_COCOA_EXIT(env);

    return ptr_to_jlong(image);
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeCreateNSImageFromFileContents
 * Signature: (Ljava/lang/String;)J
 */
JNIEXPORT jlong JNICALL Java_sun_lwawt_macosx_CImage_nativeCreateNSImageFromFileContents
(JNIEnv *env, jclass klass, jstring file)
{
    NSImage *image = nil;

JNF_COCOA_ENTER(env);

    NSString *path = JNFNormalizedNSStringForPath(env, file);
    image = [[NSImage alloc] initByReferencingFile:path];
    if (image) CFRetain(image); // GC

JNF_COCOA_EXIT(env);

    return ptr_to_jlong(image);
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeCreateNSImageOfFileFromLaunchServices
 * Signature: (Ljava/lang/String;)J
 */
JNIEXPORT jlong JNICALL Java_sun_lwawt_macosx_CImage_nativeCreateNSImageOfFileFromLaunchServices
(JNIEnv *env, jclass klass, jstring file)
{
    __block NSImage *image = nil;

JNF_COCOA_ENTER(env);

    NSString *path = JNFNormalizedNSStringForPath(env, file);
    [ThreadUtilities performOnMainThreadWaiting:YES block:^(){
        image = [[NSWorkspace sharedWorkspace] iconForFile:path];
        [image setScalesWhenResized:TRUE];
        if (image) CFRetain(image); // GC
    }];

JNF_COCOA_EXIT(env);

    return ptr_to_jlong(image);
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeCreateNSImageFromImageName
 * Signature: (Ljava/lang/String;)J
 */
JNIEXPORT jlong JNICALL Java_sun_lwawt_macosx_CImage_nativeCreateNSImageFromImageName
(JNIEnv *env, jclass klass, jstring name)
{
    NSImage *image = nil;

JNF_COCOA_ENTER(env);

    image = [NSImage imageNamed:JNFJavaToNSString(env, name)];
    if (image) CFRetain(image); // GC

JNF_COCOA_EXIT(env);

    return ptr_to_jlong(image);
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeCopyNSImageIntoArray
 * Signature: (J[III)V
 */
JNIEXPORT void JNICALL Java_sun_lwawt_macosx_CImage_nativeCopyNSImageIntoArray
(JNIEnv *env, jclass klass, jlong nsImgPtr, jintArray buffer, jint w, jint h)
{
JNF_COCOA_ENTER(env);

    NSImage *img = (NSImage *)jlong_to_ptr(nsImgPtr);
    jint *dst = (*env)->GetPrimitiveArrayCritical(env, buffer, NULL);
    if (dst) {
        CImage_CopyNSImageIntoArray(img, dst, w, h);
        (*env)->ReleasePrimitiveArrayCritical(env, buffer, dst, JNI_ABORT);
    }

JNF_COCOA_EXIT(env);
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeGetNSImageSize
 * Signature: (J)Ljava/awt/geom/Dimension2D;
 */
JNIEXPORT jobject JNICALL Java_sun_lwawt_macosx_CImage_nativeGetNSImageSize
(JNIEnv *env, jclass klass, jlong nsImgPtr)
{
    jobject size = NULL;

JNF_COCOA_ENTER(env);

    size = NSToJavaSize(env, [(NSImage *)jlong_to_ptr(nsImgPtr) size]);

JNF_COCOA_EXIT(env);

    return size;
}

/*
 * Class:     sun_lwawt_macosx_CImage
 * Method:    nativeSetNSImageSize
 * Signature: (JDD)V
 */
JNIEXPORT void JNICALL Java_sun_lwawt_macosx_CImage_nativeSetNSImageSize
(JNIEnv *env, jclass clazz, jlong image, jdouble w, jdouble h)
{
    if (!image) return;
    NSImage *i = (NSImage *)jlong_to_ptr(image);

JNF_COCOA_ENTER(env);

    [i setScalesWhenResized:TRUE];
    [i setSize:NSMakeSize(w, h)];

JNF_COCOA_EXIT(env);
}