add java.nio.channels.Channels implementation

classpath/java/nio/channels/Channels.java

@@ -0,0 +1,75 @@
+/* Copyright (c) 2010, Avian Contributors
+
+   Permission to use, copy, modify, and/or distribute this software
+   for any purpose with or without fee is hereby granted, provided
+   that the above copyright notice and this permission notice appear
+   in all copies.
+
+   There is NO WARRANTY for this software.  See license.txt for
+   details. */
+
+package java.nio.channels;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+
+public class Channels {
+  public static InputStream newInputStream(ReadableByteChannel channel) {
+    return new MyInputStream(channel);
+  }
+
+  public static OutputStream newOutputStream(WritableByteChannel channel) {
+    return new MyOutputStream(channel);
+  }
+
+  private static class MyInputStream extends InputStream {
+    private final ReadableByteChannel channel;
+
+    public MyInputStream(ReadableByteChannel channel) {
+      this.channel = channel;
+    }
+
+    public int read() throws IOException {
+      byte[] buffer = new byte[1];
+      int r = read(buffer);
+      if (r == -1) {
+        return -1;
+      } else {
+        return buffer[0] & 0xFF;
+      }
+    }
+
+    public int read(byte[] buffer, int offset, int length) throws IOException {
+      return channel.read(ByteBuffer.wrap(buffer, offset, length));
+    }
+
+    public void close() throws IOException {
+      channel.close();
+    }
+  }
+
+  private static class MyOutputStream extends OutputStream {
+    private final WritableByteChannel channel;
+
+    public MyOutputStream(WritableByteChannel channel) {
+      this.channel = channel;
+    }
+
+    public void write(int v) throws IOException {
+      byte[] buffer = new byte[] { (byte) (v & 0xFF) };
+      write(buffer);
+    }
+
+    public void write(byte[] buffer, int offset, int length)
+      throws IOException
+    {
+      channel.write(ByteBuffer.wrap(buffer, offset, length));
+    }
+
+    public void close() throws IOException {
+      channel.close();
+    }
+  }
+}