PdfDocument.cpp revision afbd0f1fef46ef0ddf633dfde0de724db3da1405 
1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "jni.h"
18#include "GraphicsJNI.h"
19#include "core_jni_helpers.h"
20#include <vector>
21
22#include "Canvas.h"
23#include "CreateJavaOutputStreamAdaptor.h"
24
25#include "SkDocument.h"
26#include "SkPicture.h"
27#include "SkPictureRecorder.h"
28#include "SkStream.h"
29#include "SkRect.h"
30
31namespace android {
32
33struct PageRecord {
34
35    PageRecord(int width, int height, const SkRect& contentRect)
36            : mPictureRecorder(new SkPictureRecorder())
37            , mPicture(NULL)
38            , mWidth(width)
39            , mHeight(height) {
40        mContentRect = contentRect;
41    }
42
43    ~PageRecord() {
44        delete mPictureRecorder;
45        if (NULL != mPicture) {
46            mPicture->unref();
47        }
48    }
49
50    SkPictureRecorder* mPictureRecorder;
51    SkPicture* mPicture;
52    const int mWidth;
53    const int mHeight;
54    SkRect mContentRect;
55};
56
57class PdfDocument {
58public:
59    PdfDocument() {
60        mCurrentPage = NULL;
61    }
62
63    SkCanvas* startPage(int width, int height,
64            int contentLeft, int contentTop, int contentRight, int contentBottom) {
65        assert(mCurrentPage == NULL);
66
67        SkRect contentRect = SkRect::MakeLTRB(
68                contentLeft, contentTop, contentRight, contentBottom);
69        PageRecord* page = new PageRecord(width, height, contentRect);
70        mPages.push_back(page);
71        mCurrentPage = page;
72
73        SkCanvas* canvas = page->mPictureRecorder->beginRecording(
74                SkRect::MakeWH(contentRect.width(), contentRect.height()));
75
76        return canvas;
77    }
78
79    void finishPage() {
80        assert(mCurrentPage != NULL);
81        assert(mCurrentPage->mPictureRecorder != NULL);
82        assert(mCurrentPage->mPicture == NULL);
83        mCurrentPage->mPicture = mCurrentPage->mPictureRecorder->endRecording();
84        delete mCurrentPage->mPictureRecorder;
85        mCurrentPage->mPictureRecorder = NULL;
86        mCurrentPage = NULL;
87    }
88
89    void write(SkWStream* stream) {
90        SkDocument* document = SkDocument::CreatePDF(stream);
91        for (unsigned i = 0; i < mPages.size(); i++) {
92            PageRecord* page =  mPages[i];
93
94            SkCanvas* canvas = document->beginPage(page->mWidth, page->mHeight,
95                    &(page->mContentRect));
96
97            canvas->drawPicture(page->mPicture);
98
99            document->endPage();
100        }
101        document->close();
102    }
103
104    void close() {
105        assert(NULL == mCurrentPage);
106        for (unsigned i = 0; i < mPages.size(); i++) {
107            delete mPages[i];
108        }
109    }
110
111private:
112    ~PdfDocument() {
113        close();
114    }
115
116    std::vector<PageRecord*> mPages;
117    PageRecord* mCurrentPage;
118};
119
120static jlong nativeCreateDocument(JNIEnv* env, jobject thiz) {
121    return reinterpret_cast<jlong>(new PdfDocument());
122}
123
124static jlong nativeStartPage(JNIEnv* env, jobject thiz, jlong documentPtr,
125        jint pageWidth, jint pageHeight,
126        jint contentLeft, jint contentTop, jint contentRight, jint contentBottom) {
127    PdfDocument* document = reinterpret_cast<PdfDocument*>(documentPtr);
128    SkCanvas* canvas = document->startPage(pageWidth, pageHeight,
129            contentLeft, contentTop, contentRight, contentBottom);
130    return reinterpret_cast<jlong>(Canvas::create_canvas(canvas));
131}
132
133static void nativeFinishPage(JNIEnv* env, jobject thiz, jlong documentPtr) {
134    PdfDocument* document = reinterpret_cast<PdfDocument*>(documentPtr);
135    document->finishPage();
136}
137
138static void nativeWriteTo(JNIEnv* env, jobject thiz, jlong documentPtr, jobject out,
139        jbyteArray chunk) {
140    PdfDocument* document = reinterpret_cast<PdfDocument*>(documentPtr);
141    SkWStream* skWStream = CreateJavaOutputStreamAdaptor(env, out, chunk);
142    document->write(skWStream);
143    delete skWStream;
144}
145
146static void nativeClose(JNIEnv* env, jobject thiz, jlong documentPtr) {
147    PdfDocument* document = reinterpret_cast<PdfDocument*>(documentPtr);
148    document->close();
149}
150
151static const JNINativeMethod gPdfDocument_Methods[] = {
152    {"nativeCreateDocument", "()J", (void*) nativeCreateDocument},
153    {"nativeStartPage", "(JIIIIII)J", (void*) nativeStartPage},
154    {"nativeFinishPage", "(J)V", (void*) nativeFinishPage},
155    {"nativeWriteTo", "(JLjava/io/OutputStream;[B)V", (void*) nativeWriteTo},
156    {"nativeClose", "(J)V", (void*) nativeClose}
157};
158
159int register_android_graphics_pdf_PdfDocument(JNIEnv* env) {
160    return RegisterMethodsOrDie(
161            env, "android/graphics/pdf/PdfDocument", gPdfDocument_Methods,
162            NELEM(gPdfDocument_Methods));
163}
164
165};
166