epub读取优化&Bitmap解码优化

导入epub优化，复制文件到缓存区域，使用ZipFile代替ZipInputStream,使得读取能懒加载epub，减少读取epub时的内存占用。
使用BitmapFactory.decodeStream代替BitmapFactory.decodeFile,来减少加载图片时产生OOM的可能性。

app/src/main/java/io/legado/app/help/BookHelp.kt

@@ -21,9 +21,9 @@ import kotlin.math.max
 import kotlin.math.min
 
 object BookHelp {
-    private const val cacheFolderName = "book_cache"
+    const val cacheFolderName = "book_cache"
     private const val cacheImageFolderName = "images"
-    private val downloadDir: File = appCtx.externalFilesDir
+    val downloadDir: File = appCtx.externalFilesDir
     private val downloadImages = CopyOnWriteArraySet<String>()
 
     fun clearCache() {

app/src/main/java/io/legado/app/model/localBook/EpubFile.kt

@@ -6,12 +6,10 @@ import android.net.Uri
 import android.text.TextUtils
 import io.legado.app.data.entities.Book
 import io.legado.app.data.entities.BookChapter
+import io.legado.app.help.BookHelp
 import io.legado.app.utils.*
 import me.ag2s.epublib.domain.EpubBook
-import me.ag2s.epublib.domain.MediaTypes
-import me.ag2s.epublib.domain.Resources
 import me.ag2s.epublib.epub.EpubReader
-import me.ag2s.epublib.util.ResourceUtil
 import org.jsoup.Jsoup
 import splitties.init.appCtx
 import java.io.File
@@ -20,8 +18,7 @@ import java.io.IOException
 import java.io.InputStream
 import java.nio.charset.Charset
 import java.util.*
-import java.util.zip.ZipEntry
-import java.util.zip.ZipInputStream
+import java.util.zip.ZipFile
 
 class EpubFile(var book: Book) {
 
@@ -101,32 +98,46 @@ class EpubFile(var book: Book) {
     /*重写epub文件解析代码，直接读出压缩包文件生成Resources给epublib，这样的好处是可以逐一修改某些文件的格式错误*/
     private fun readEpub(): EpubBook? {
         try {
-            val input = if (book.bookUrl.isContentScheme()) {
-                val uri = Uri.parse(book.bookUrl)
-                appCtx.contentResolver.openInputStream(uri)
-            } else {
-                File(book.bookUrl).inputStream()
-            }
-            input ?: return null
-            val inZip = ZipInputStream(input)
-            var zipEntry: ZipEntry?
-            val resources = Resources()
-            do {
-                zipEntry = inZip.nextEntry
-                if ((zipEntry == null) || zipEntry.isDirectory || zipEntry == ZipEntry("<error>")) continue
-                val resource = ResourceUtil.createResource(zipEntry, inZip)
-                if (resource.mediaType == MediaTypes.XHTML) resource.inputEncoding = "UTF-8"
-                if (zipEntry.name.endsWith(".opf")) {
-                    /*掌上书苑有很多自制书OPF的nameSpace格式不标准，强制修复成正确的格式*/
-                    val newS = String(resource.data).replace(
-                        "\\smlns=\"http://www.idpf.org/2007/opf\"".toRegex(),
-                        " xmlns=\"http://www.idpf.org/2007/opf\""
-                    )
-                    resource.data = newS.toByteArray()
+            //f
+            val file = FileUtils.getFile(
+                BookHelp.downloadDir,
+                BookHelp.cacheFolderName,
+                book.getFolderName(),
+                "index.epubx"
+            )
+            if (!file.exists()) {
+                val input = if (book.bookUrl.isContentScheme()) {
+                    val uri = Uri.parse(book.bookUrl)
+                    appCtx.contentResolver.openInputStream(uri)
+                } else {
+                    File(book.bookUrl).inputStream()
                 }
-                resources.add(resource)
-            } while (zipEntry != null)
-            if (resources.size() > 0) return EpubReader().readEpub(resources)
+                input ?: return null
+                FileUtils.writeInputStream(file, input)
+
+            }
+            return EpubReader().readEpubLazy(ZipFile(file),"utf-8")
+
+
+//            val inZip = ZipInputStream(input)
+//            var zipEntry: ZipEntry?
+//            val resources = Resources()
+//            do {
+//                zipEntry = inZip.nextEntry
+//                if ((zipEntry == null) || zipEntry.isDirectory || zipEntry == ZipEntry("<error>")) continue
+//                val resource = ResourceUtil.createResource(zipEntry, inZip)
+//                if (resource.mediaType == MediaTypes.XHTML) resource.inputEncoding = "UTF-8"
+//                if (zipEntry.name.endsWith(".opf")) {
+//                    /*掌上书苑有很多自制书OPF的nameSpace格式不标准，强制修复成正确的格式*/
+//                    val newS = String(resource.data).replace(
+//                        "\\smlns=\"http://www.idpf.org/2007/opf\"".toRegex(),
+//                        " xmlns=\"http://www.idpf.org/2007/opf\""
+//                    )
+//                    resource.data = newS.toByteArray()
+//                }
+//                resources.add(resource)
+//            } while (zipEntry != null)
+//            if (resources.size() > 0) return EpubReader().readEpub(resources)
         } catch (e: Exception) {
             e.printStackTrace()
         }

app/src/main/java/io/legado/app/ui/book/read/page/provider/ImageProvider.kt

@@ -54,7 +54,9 @@ object ImageProvider {
                 ChapterProvider.visibleWidth,
                 ChapterProvider.visibleHeight
             )
-            setCache(chapterIndex, src, bitmap)
+            if (bitmap != null) {
+                setCache(chapterIndex, src, bitmap)
+            }
             bitmap
         } catch (e: Exception) {
             null

app/src/main/java/io/legado/app/utils/BitmapUtils.kt

@@ -9,6 +9,7 @@ import android.renderscript.RenderScript
 import android.renderscript.ScriptIntrinsicBlur
 import android.view.View
 import splitties.init.appCtx
+import java.io.FileInputStream
 import java.io.IOException
 import kotlin.math.*
 
@@ -25,11 +26,12 @@ object BitmapUtils {
      * @param height 想要显示的图片的高度
      * @return
      */
-    fun decodeBitmap(path: String, width: Int, height: Int): Bitmap {
+    fun decodeBitmap(path: String, width: Int, height: Int): Bitmap? {
         val op = BitmapFactory.Options()
+        var ips=FileInputStream(path)
         // inJustDecodeBounds如果设置为true,仅仅返回图片实际的宽和高,宽和高是赋值给opts.outWidth,opts.outHeight;
         op.inJustDecodeBounds = true
-        BitmapFactory.decodeFile(path, op) //获取尺寸信息
+        BitmapFactory.decodeStream(ips,null,op)//获取尺寸信息
         //获取比例大小
         val wRatio = ceil((op.outWidth / width).toDouble()).toInt()
         val hRatio = ceil((op.outHeight / height).toDouble()).toInt()
@@ -41,22 +43,24 @@ object BitmapUtils {
                 op.inSampleSize = hRatio
             }
         }
+        ips=FileInputStream(path)
         op.inJustDecodeBounds = false
-        return BitmapFactory.decodeFile(path, op)
+        return BitmapFactory.decodeStream(ips,null,op)
     }
 
     /** 从path中获取Bitmap图片
      * @param path 图片路径
      * @return
      */
-    fun decodeBitmap(path: String): Bitmap {
+    fun decodeBitmap(path: String): Bitmap? {
         val opts = BitmapFactory.Options()
+        var ips=FileInputStream(path)
         opts.inJustDecodeBounds = true
-        BitmapFactory.decodeFile(path, opts)
+        BitmapFactory.decodeStream(ips,null,opts)
         opts.inSampleSize = computeSampleSize(opts, -1, 128 * 128)
         opts.inJustDecodeBounds = false
-
-        return BitmapFactory.decodeFile(path, opts)
+        ips=FileInputStream(path)
+        return  BitmapFactory.decodeStream(ips,null,opts)
     }
 
     /**

app/src/main/java/io/legado/app/utils/FileUtils.kt

@@ -517,6 +517,44 @@ object FileUtils {
             closeSilently(fos)
         }
     }
+    /**
+     * 保存文件内容
+     */
+    fun writeInputStream(filepath: String, data: InputStream): Boolean {
+        val file = File(filepath)
+        return writeInputStream(file,data)
+    }
+
+    /**
+     * 保存文件内容
+     */
+    fun writeInputStream(file: File, data: InputStream): Boolean {
+        var fos: FileOutputStream? = null
+        return try {
+            if (!file.exists()) {
+                file.parentFile?.mkdirs()
+                file.createNewFile()
+            }
+            val buffer=ByteArray(1024*4)
+            fos = FileOutputStream(file)
+            while (true) {
+                val len = data.read(buffer, 0, buffer.size)
+                if (len == -1) {
+                    break
+                } else {
+                    fos.write(buffer, 0, len)
+                }
+            }
+            data.close()
+            fos.flush()
+
+            true
+        } catch (e: IOException) {
+            false
+        } finally {
+            closeSilently(fos)
+        }
+    }
 
     /**
      * 追加文本内容