Merge pull request #8125 from eugenp/revert-8119-BAEL-3275-2

Revert "BAEL-3275: Using blocking queue for pub-sub"

libraries/src/test/java/com/baeldung/streamutils/CopyStreamUnitTest.java

@@ -0,0 +1,100 @@
+package com.baeldung.streamutils;
+
+import static org.junit.Assert.assertTrue;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.springframework.util.StreamUtils;
+
+import static com.baeldung.streamutils.CopyStream.getStringFromInputStream;
+
+public class CopyStreamUnitTest {
+
+    @Test
+    public void whenCopyInputStreamToOutputStream_thenCorrect() throws IOException {
+        String inputFileName = "src/test/resources/input.txt";
+        String outputFileName = "src/test/resources/output.txt";
+        File outputFile = new File(outputFileName);
+        InputStream in = new FileInputStream(inputFileName);
+        OutputStream out = new FileOutputStream(outputFileName);
+
+        StreamUtils.copy(in, out);
+
+        assertTrue(outputFile.exists());
+        String inputFileContent = getStringFromInputStream(new FileInputStream(inputFileName));
+        String outputFileContent = getStringFromInputStream(new FileInputStream(outputFileName));
+        Assert.assertEquals(inputFileContent, outputFileContent);
+    }
+
+    @Test
+    public void whenCopyRangeOfInputStreamToOutputStream_thenCorrect() throws IOException {
+        String inputFileName = "src/test/resources/input.txt";
+        String outputFileName = "src/test/resources/output.txt";
+        File outputFile = new File(outputFileName);
+        InputStream in = new FileInputStream(inputFileName);
+        OutputStream out = new FileOutputStream(outputFileName);
+
+        StreamUtils.copyRange(in, out, 1, 10);
+
+        assertTrue(outputFile.exists());
+        String inputFileContent = getStringFromInputStream(new FileInputStream(inputFileName));
+        String outputFileContent = getStringFromInputStream(new FileInputStream(outputFileName));
+        Assert.assertEquals(inputFileContent.substring(1, 11), outputFileContent);
+    }
+
+    @Test
+    public void whenCopyStringToOutputStream_thenCorrect() throws IOException {
+        String string = "Should be copied to OutputStream.";
+        String outputFileName = "src/test/resources/output.txt";
+        File outputFile = new File(outputFileName);
+        OutputStream out = new FileOutputStream("src/test/resources/output.txt");
+
+        StreamUtils.copy(string, StandardCharsets.UTF_8, out);
+
+        assertTrue(outputFile.exists());
+        String outputFileContent = getStringFromInputStream(new FileInputStream(outputFileName));
+        Assert.assertEquals(outputFileContent, string);
+    }
+
+    @Test
+    public void whenCopyInputStreamToString_thenCorrect() throws IOException {
+        String inputFileName = "src/test/resources/input.txt";
+        InputStream is = new FileInputStream(inputFileName);
+        String content = StreamUtils.copyToString(is, StandardCharsets.UTF_8);
+
+        String inputFileContent = getStringFromInputStream(new FileInputStream(inputFileName));
+        Assert.assertEquals(inputFileContent, content);
+    }
+
+    @Test
+    public void whenCopyByteArrayToOutputStream_thenCorrect() throws IOException {
+        String outputFileName = "src/test/resources/output.txt";
+        String string = "Should be copied to OutputStream.";
+        byte[] byteArray = string.getBytes();
+        OutputStream out = new FileOutputStream("src/test/resources/output.txt");
+
+        StreamUtils.copy(byteArray, out);
+        String outputFileContent = getStringFromInputStream(new FileInputStream(outputFileName));
+        Assert.assertEquals(outputFileContent, string);
+    }
+
+    @Test
+    public void whenCopyInputStreamToByteArray_thenCorrect() throws IOException {
+        String inputFileName = "src/test/resources/input.txt";
+        InputStream in = new FileInputStream(inputFileName);
+        byte[] out = StreamUtils.copyToByteArray(in);
+
+        String content = new String(out);
+        String inputFileContent = getStringFromInputStream(new FileInputStream(inputFileName));
+        Assert.assertEquals(inputFileContent, content);
+    }
+
+}