Use a7zip to extract archives

app/src/main/java/com/hippo/ehviewer/gallery/Pipe.java

@@ -0,0 +1,160 @@
+/*
+ * Copyright 2019 Hippo Seven
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.hippo.ehviewer.gallery;
+
+import android.support.annotation.NonNull;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+class Pipe {
+
+  private final int capacity;
+  private final byte[] buffer;
+
+  private int head = 0;
+  private int tail = 0;
+  private boolean full = false;
+
+  private boolean inClosed = false;
+  private boolean outClosed = false;
+
+  private InputStream inputStream = new InputStream() {
+    @Override
+    public int read() throws IOException {
+      synchronized (Pipe.this) {
+        byte[] bytes = new byte[1];
+        if (read(bytes, 0, 1) != -1) {
+          return bytes[0];
+        } else {
+          return -1;
+        }
+      }
+    }
+
+    @Override
+    public int read(@NonNull byte[] b, int off, int len) throws IOException {
+      synchronized (Pipe.this) {
+        for (;;) {
+          if (inClosed) {
+            throw new IOException("The InputStream is closed");
+          }
+          if (len == 0) {
+            return 0;
+          }
+
+          if (head == tail && !full) {
+            if (outClosed) {
+              // No bytes available and the OutputStream is closed. So it's the end.
+              return -1;
+            } else {
+              // Wait for OutputStream write bytes
+              try {
+                Pipe.this.wait();
+              } catch (InterruptedException e) {
+                throw new IOException("The thread interrupted", e);
+              }
+            }
+          } else {
+            int read = Math.min(len, (head < tail ? tail : capacity) - head);
+            System.arraycopy(buffer, head, b, off, read);
+            head += read;
+            if (head == capacity) {
+              head = 0;
+            }
+            full = false;
+            Pipe.this.notifyAll();
+            return read;
+          }
+        }
+      }
+    }
+
+    @Override
+    public void close() {
+      synchronized (Pipe.this) {
+        inClosed = true;
+      }
+    }
+  };
+
+  private OutputStream outputStream = new OutputStream() {
+    @Override
+    public void write(int b) throws IOException {
+      synchronized (Pipe.this) {
+        byte[] bytes = new byte[] { (byte) b};
+        write(bytes, 0, 1);
+      }
+    }
+
+    @Override
+    public void write(@NonNull byte[] b, int off, int len) throws IOException {
+      synchronized (Pipe.this) {
+        while (len != 0) {
+          if (outClosed) {
+            throw new IOException("The OutputStream is closed");
+          }
+          if (inClosed) {
+            throw new IOException("The InputStream is closed");
+          }
+
+          if (head == tail && full) {
+            // The buffer is full, wait for InputStream read bytes
+            try {
+              Pipe.this.wait();
+            } catch (InterruptedException e) {
+              throw new IOException("The thread interrupted", e);
+            }
+          } else {
+            int write = Math.min(len, (head <= tail ? capacity : head) - tail);
+            System.arraycopy(b, off, buffer, tail, write);
+            off += write;
+            len -= write;
+            tail += write;
+            if (tail == capacity) {
+              tail = 0;
+            }
+            if (head == tail) {
+              full = true;
+            }
+            Pipe.this.notifyAll();
+          }
+        }
+      }
+    }
+
+    @Override
+    public void close() {
+      synchronized (Pipe.this) {
+        outClosed = true;
+      }
+    }
+  };
+
+  Pipe(int capacity) {
+    this.capacity = capacity;
+    this.buffer = new byte[capacity];
+  }
+
+  InputStream getInputStream() {
+    return inputStream;
+  }
+
+  OutputStream getOutputStream() {
+    return outputStream;
+  }
+}