Add SocketUtils

Author: Artem Labazin

CHANGELOG.md

@@ -10,6 +10,18 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ## [Unreleased]
 
 - Add more tests.
+- Add `JavaDoc`.
+
+## [1.2.0](https://github.com/appulse-projects/utils-java/releases/tag/1.2.0) - 2018-02-01
+
+### Added
+
+- Method `array(int)` in `Bytes` for getting `byte[]` with offset.
+- Added port related functions to `StreamReader`.
+
+### Changed
+
+- Renamed `StreamReader` to `SocketUtils`.
 
 ## [1.1.0](https://github.com/appulse-projects/utils-java/releases/tag/1.1.0) - 2018-01-30
 

pom.xml

@@ -24,7 +24,7 @@ limitations under the License.
 
   <groupId>io.appulse</groupId>
   <artifactId>utils-java</artifactId>
-  <version>1.1.0</version>
+  <version>1.2.0</version>
   <packaging>jar</packaging>
 
   <properties>
@@ -62,7 +62,7 @@ limitations under the License.
     <url>https://github.com/appulse-projects/utils-java</url>
     <connection>scm:git:https://github.com/appulse-projects/utils-java.git</connection>
     <developerConnection>scm:git:https://github.com/appulse-projects/utils-java.git</developerConnection>
-    <tag>1.1.0</tag>
+    <tag>1.2.0</tag>
   </scm>
 
   <distributionManagement>

src/main/java/io/appulse/utils/Bytes.java

@@ -131,6 +131,24 @@ public byte[] array () {
     return Arrays.copyOfRange(buffer.array(), 0, limit);
   }
 
+  /**
+   * Returns byte array representation of class, starting from specified position.
+   *
+   * @param offset start position
+   *
+   * @return byte array representation
+   *
+   * @throws IndexOutOfBoundsException if offset is lower zero or larger the limit
+   *
+   * @since 1.2.0
+   */
+  public byte[] array (int offset) {
+    if (offset < 0 || offset > limit) {
+      throw new IndexOutOfBoundsException();
+    }
+    return Arrays.copyOfRange(buffer.array(), offset, limit);
+  }
+
   public int limit () {
     return limit;
   }

…/java/io/appulse/utils/StreamReader.java …n/java/io/appulse/utils/SocketUtils.javasrc/main/java/io/appulse/utils/StreamReader.java renamed to src/main/java/io/appulse/utils/SocketUtils.java src/main/java/io/appulse/utils/StreamReader.java renamed to src/main/java/io/appulse/utils/SocketUtils.java

@@ -16,10 +16,17 @@
 
 package io.appulse.utils;
 
+import static java.util.Optional.empty;
+import static java.util.Optional.of;
+import static java.util.concurrent.TimeUnit.SECONDS;
+
 import java.io.ByteArrayOutputStream;
 import java.io.EOFException;
+import java.io.IOException;
 import java.io.InputStream;
+import java.net.InetSocketAddress;
 import java.net.Socket;
+import java.util.Optional;
 
 import lombok.NonNull;
 import lombok.SneakyThrows;
@@ -28,9 +35,31 @@
 /**
  *
  * @author Artem Labazin
- * @since 1.1.0
+ * @since 1.2.0
  */
-public final class StreamReader {
+public final class SocketUtils {
+
+  public static Optional<Integer> findFreePort () {
+    return findFreePort(1024, 65535);
+  }
+
+  public static Optional<Integer> findFreePort (int from, int to) {
+    for (int port = from; port <= to; port++) {
+      if (isPortAvailable(port)) {
+        return of(port);
+      }
+    }
+    return empty();
+  }
+
+  public static boolean isPortAvailable (int port) {
+    try (Socket socket = new Socket()) {
+      socket.connect(new InetSocketAddress("localhost", port), (int) SECONDS.toMillis(1));
+      return false;
+    } catch (IOException ex) {
+      return true;
+    }
+  }
 
   @SneakyThrows
   public static byte[] read (@NonNull InputStream stream) {
@@ -98,6 +127,6 @@ public static Bytes readBytes (@NonNull Socket socket, int fixedLength) {
     return readBytes(socket.getInputStream(), fixedLength);
   }
 
-  private StreamReader () {
+  private SocketUtils () {
   }
 }

…a/io/appulse/utils/StreamReaderTest.java …va/io/appulse/utils/SocketUtilsTest.javasrc/test/java/io/appulse/utils/StreamReaderTest.java renamed to src/test/java/io/appulse/utils/SocketUtilsTest.java src/test/java/io/appulse/utils/StreamReaderTest.java renamed to src/test/java/io/appulse/utils/SocketUtilsTest.java

@@ -21,6 +21,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Arrays;
+import java.util.Optional;
 
 import org.junit.Test;
 
@@ -30,15 +31,22 @@
 /**
  *
  * @author Artem Labazin
- * @since 1.1.0
+ * @since 1.2.0
  */
-public class StreamReaderTest {
+public class SocketUtilsTest {
+
+  @Test
+  public void isPortAvailable () {
+    Optional<Integer> port = SocketUtils.findFreePort();
+    assertThat(port).isPresent();
+    assertThat(SocketUtils.isPortAvailable(port.get())).isTrue();
+  }
 
   @Test
   public void read () throws Exception {
     byte[] expected = "Hello world".getBytes();
 
-    assertThat(StreamReader.read(new CustomInputStream(expected)))
+    assertThat(SocketUtils.read(new CustomInputStream(expected)))
         .isEqualTo(expected);
   }
 
@@ -47,7 +55,7 @@ public void readWithLength () throws Exception {
     byte[] bytes = "Hello world".getBytes();
     byte[] expected = Arrays.copyOfRange(bytes, 0, 2);
 
-    assertThat(StreamReader.read(new CustomInputStream(bytes), 2))
+    assertThat(SocketUtils.read(new CustomInputStream(bytes), 2))
         .isEqualTo(expected);
   }