yegor256#377: Added TkProxy class.

src/main/java/org/takes/tk/TkProxy.java

@@ -0,0 +1,144 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.takes.tk;
+
+import java.io.IOException;
+import lombok.EqualsAndHashCode;
+import lombok.ToString;
+import org.takes.Request;
+import org.takes.Response;
+import org.takes.Take;
+
+/**
+ * Proxy take.
+ *
+ * <p>This take may transform the request before passing it
+ * to the original take and/or transform the response received
+ * from the original take.
+ *
+ * <p>If the request transformer is not provided, the original
+ * request is passed to the original take.
+ *
+ * <p>If the response transformer is not provided, the response
+ * received from the original take is returned.
+ *
+ * <p>The class is immutable and thread-safe.
+ *
+ * @author Dragan Bozanovic ([email protected])
+ * @version $Id$
+ * @since 0.25
+ */
+@ToString
+@EqualsAndHashCode
+public final class TkProxy implements Take {
+
+    /**
+     * Original take.
+     */
+    private final transient Take origin;
+
+    /**
+     * Request transformer.
+     */
+    private final transient RqTransformer rqtransformer;
+
+    /**
+     * Response transformer.
+     */
+    private final transient RsTransformer rstransformer;
+
+    /**
+     * Ctor.
+     * @param take Original take
+     * @param rqtransformr Request transformer
+     * @param rstransformr Response transformer
+     */
+    public TkProxy(final Take take, final RqTransformer rqtransformr,
+            final RsTransformer rstransformr) {
+        this.origin = take;
+        this.rqtransformer = rqtransformr;
+        this.rstransformer = rstransformr;
+    }
+
+    /**
+     * Ctor.
+     * @param take Original take
+     * @param rqtransformr Request transformer
+     */
+    public TkProxy(final Take take, final RqTransformer rqtransformr) {
+        this(take, rqtransformr, new RsTransformer() {
+            @Override
+            public Response transform(final Response response) {
+                return response;
+            }
+        });
+    }
+
+    /**
+     * Ctor.
+     * @param take Original take
+     * @param rstransformr Response transformer
+     */
+    public TkProxy(final Take take, final RsTransformer rstransformr) {
+        this(take, new RqTransformer() {
+            @Override
+            public Request transform(final Request request) {
+                return request;
+            }
+        }, rstransformr);
+    }
+
+    @Override
+    public Response act(final Request req) throws IOException {
+        final Request transformed = this.rqtransformer.transform(req);
+        final Response response = this.origin.act(transformed);
+        return this.rstransformer.transform(response);
+    }
+
+    /**
+     * Request transformer.
+     */
+    public interface RqTransformer {
+
+        /**
+         * Transforms the original request.
+         * @param request Original request
+         * @return The transformed request
+         */
+        Request transform(Request request);
+    }
+
+    /**
+     * Response transformer.
+     */
+    public interface RsTransformer {
+
+        /**
+         * Transforms the original response.
+         * @param response Original response
+         * @return Transformed response
+         */
+        Response transform(Response response);
+    }
+}

src/test/java/org/takes/tk/TkProxyTest.java

@@ -0,0 +1,96 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.takes.tk;
+
+import java.io.IOException;
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
+import org.junit.Test;
+import org.mockito.Mockito;
+import org.takes.Request;
+import org.takes.Response;
+import org.takes.Take;
+import org.takes.rq.RqFake;
+import org.takes.tk.TkProxy.RqTransformer;
+import org.takes.tk.TkProxy.RsTransformer;
+
+/**
+ * Test case for {@link org.takes.tk.TkProxy1}.
+ * @author Dragan Bozanovic ([email protected])
+ * @version $Id$
+ * @since 0.25
+ */
+public final class TkProxyTest {
+
+    /**
+     * TkProxy can proxy requests.
+     * @throws IOException If some problem inside
+     */
+    @Test
+    public void proxiesRequest() throws IOException {
+        final Take take = Mockito.mock(Take.class);
+        final Request transformed = Mockito.mock(Request.class);
+        final Response response = Mockito.mock(Response.class);
+        Mockito.when(take.act(transformed)).thenReturn(response);
+        final TkProxy tkProxy = new TkProxy(
+            take,
+            new RqTransformer() {
+                @Override
+                public Request transform(final Request request) {
+                    return transformed;
+                }
+            }
+         );
+        MatcherAssert.assertThat(
+            tkProxy.act(new RqFake()),
+            Matchers.equalTo(response)
+        );
+        Mockito.verify(take).act(transformed);
+    }
+
+    /**
+     * TkProxy can proxy responses.
+     * @throws IOException If some problem inside
+     */
+    @Test
+    public void proxiesResponse() throws IOException {
+        final Take take = Mockito.mock(Take.class);
+        final Request request = Mockito.mock(Request.class);
+        final Response transformed = Mockito.mock(Response.class);
+        final TkProxy tkProxy = new TkProxy(
+            take,
+            new RsTransformer() {
+                @Override
+                public Response transform(final Response response) {
+                    return transformed;
+                }
+            }
+        );
+        MatcherAssert.assertThat(
+            tkProxy.act(request),
+            Matchers.equalTo(transformed)
+        );
+        Mockito.verify(take).act(request);
+    }
+}