FEAT StreamUtils: inputStreamToByteArray + pipeStream

README.md

@@ -1,4 +1,4 @@
-# de.nclazz Java-Commons
+# java-commons
 [![Build Status](https://jenkins.niclas-thobaben.de/buildStatus/icon?job=de.nclazz%2Fjava-commons%2Fmaster)](https://jenkins.niclas-thobaben.de/job/de.nclazz/job/java-commons/job/master/)
 
 

pom.xml

@@ -7,7 +7,7 @@
     <groupId>de.nclazz</groupId>
     <artifactId>commons</artifactId>
     <version>1.0.0-SNAPSHOT</version>
-    
+
     <parent>
         <groupId>de.nclazz</groupId>
         <artifactId>maven-boot</artifactId>

src/main/java/de/nclazz/commons/io/StreamUtils.java

@@ -0,0 +1,46 @@
+package de.nclazz.commons.io;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public abstract class StreamUtils {
+
+    private StreamUtils() { /* no-op */ }
+
+    /**
+     * Pipes all the input from {@code streamIn} to {@code streamOut}.
+     * This method does not close any of the streams!
+     *
+     * @param streamIn InputStream
+     * @param streamOut OutputStream
+     * @throws IOException
+     */
+    public static void pipeStream(InputStream streamIn, OutputStream streamOut) throws IOException {
+        byte[] bytes = new byte[4096]; //TODO make configurable? maybe as a sys property?
+        int length;
+        while ((length = streamIn.read(bytes)) >= 0) {
+            streamOut.write(bytes, 0, length);
+        }
+    }
+
+    /**
+     * Loads an InputStream into a new byte array.
+     * This method does not close the stream after processing!
+     * @param stream InputStream
+     * @return new {@code byte[]}
+     */
+    public static byte[] inputStreamToByteArray(InputStream stream) throws IOException {
+        ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        byte[] buffer = new byte[4096]; //TODO make configurable? maybe as a sys property?
+        int length;
+        while((length = stream.read(buffer)) != -1) {
+            bos.write(buffer, 0, length);
+        }
+        return bos.toByteArray();
+    }
+
+
+
+}

src/test/java/de/nclazz/commons/io/StreamUtilsTests.java

@@ -0,0 +1,40 @@
+package de.nclazz.commons.io;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Arrays;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class StreamUtilsTests {
+
+    byte[] alphabetBytes = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p',
+                            'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F',
+                            'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V',
+                            'W', 'X', 'Y', 'Z',  };
+
+    @Test
+    void testInputStreamToByteArray() throws IOException {
+
+        InputStream stream = StreamUtilsTests.class.getResourceAsStream("/test-files/alphabet-utf8.txt");
+        byte[] bytes = StreamUtils.inputStreamToByteArray(stream);
+
+        assertTrue(Arrays.equals(alphabetBytes, bytes));
+    }
+
+    @Test
+    void testStreamPiping() throws IOException {
+        ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        InputStream stream = StreamUtilsTests.class.getResourceAsStream("/test-files/alphabet-utf8.txt");
+
+        StreamUtils.pipeStream(stream, bos);
+        byte[] bytes = bos.toByteArray();
+
+        assertTrue(Arrays.equals(alphabetBytes, bytes));
+    }
+
+}

src/test/resources/test-files/alphabet-utf8.txt

@@ -0,0 +1 @@
+abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ