Add more examples

src/test/java/io/netty/buffer/api/examples/AsyncExample.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2020 The Netty Project
+ *
+ * The Netty Project licenses this file to you 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:
+ *
+ *   https://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 io.netty.buffer.api.examples;
+
+import io.netty.buffer.api.Allocator;
+import io.netty.buffer.api.Buf;
+
+import static java.util.concurrent.CompletableFuture.completedFuture;
+
+public final class AsyncExample {
+    public static void main(String[] args) throws Exception {
+        try (Allocator allocator = Allocator.pooledDirectWithCleaner();
+             Buf startBuf = allocator.allocate(16)) {
+            startBuf.writeLong(threadId());
+
+            completedFuture(startBuf.send()).thenApplyAsync(send -> {
+                try (Buf buf = send.receive()) {
+                    buf.writeLong(threadId());
+                    return buf.send();
+                }
+            }).thenAcceptAsync(send -> {
+                try (Buf buf = send.receive()) {
+                    System.out.println("First thread id was " + buf.readLong());
+                    System.out.println("Then sent to " + buf.readLong());
+                    System.out.println("And now in thread " + threadId());
+                }
+            }).get();
+        }
+    }
+
+    private static long threadId() {
+        return Thread.currentThread().getId();
+    }
+}

src/test/java/io/netty/buffer/api/examples/ComposingAndSlicingExample.java

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+/*
+ * Copyright 2020 The Netty Project
+ *
+ * The Netty Project licenses this file to you 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:
+ *
+ *   https://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 io.netty.buffer.api.examples;
+
+import io.netty.buffer.api.Allocator;
+import io.netty.buffer.api.Buf;
+import io.netty.buffer.api.Scope;
+
+import java.util.concurrent.ThreadLocalRandom;
+
+public final class ComposingAndSlicingExample {
+    public static void main(String[] args) {
+        try (Allocator allocator = Allocator.pooledDirect();
+             Buf buf = createBigBuffer(allocator)) {
+
+            ThreadLocalRandom tlr = ThreadLocalRandom.current();
+            for (int i = 0; i < tlr.nextInt(4, 200); i++) {
+                buf.writeByte((byte) tlr.nextInt());
+            }
+
+            try (Buf slice = buf.slice()) {
+                slice.send();
+                System.out.println("buf.capacity() = " + buf.capacity());
+                System.out.println("buf.readableBytes() = " + buf.readableBytes());
+                System.out.println("---");
+                System.out.println("slice.capacity() = " + slice.capacity());
+                System.out.println("slice.readableBytes() = " + slice.readableBytes());
+            }
+        }
+    }
+
+    private static Buf createBigBuffer(Allocator allocator) {
+        try (Scope scope = new Scope()) {
+            return allocator.compose(
+                    scope.add(allocator.allocate(64)),
+                    scope.add(allocator.allocate(64)),
+                    scope.add(allocator.allocate(64)),
+                    scope.add(allocator.allocate(64)));
+        }
+    }
+}