Added tests for FileUtils.

aksw-commons-io-parent/aksw-commons-io-utils/src/test/java/org/aksw/commons/io/util/FileUtilsTest.java

@@ -0,0 +1,68 @@
+package org.aksw.commons.io.util;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.FileAlreadyExistsException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import org.aksw.commons.io.util.FileUtils.OverwritePolicy;
+import org.junit.Assert;
+import org.junit.Test;
+
+
+public class FileUtilsTest {
+    public static final String TEST_STRING = "Hello";
+
+    @Test
+    public void test_safeCreate_00() throws Exception {
+        Path path = Files.createTempFile("test", ".tmp");
+        writeTestFileAndAssert(path, OverwritePolicy.SKIP, TEST_STRING, "");
+    }
+
+    @Test
+    public void test_safeCreate_01() throws Exception {
+        Path path = Files.createTempFile("test", ".tmp");
+        writeTestFileAndAssert(path, OverwritePolicy.OVERWRITE);
+    }
+
+    @Test
+    public void test_safeCreate_02() throws Exception {
+        Path path = Files.createTempFile("test", ".tmp");
+        writeTestFileAndAssert(path, OverwritePolicy.OVERWRITE_ALWAYS);
+    }
+
+    @Test(expected = FileAlreadyExistsException.class)
+    public void test_safeCreate_03() throws Exception {
+        Path path = Files.createTempFile("test", ".tmp");
+        writeTestFileAndAssert(path, OverwritePolicy.ERROR);
+    }
+
+    public void writeTestFileAndAssert(Path path, OverwritePolicy overwritePolicy, String writeStr, String assertStr) throws Exception {
+        try {
+            FileUtils.safeCreate(path, overwritePolicy, out -> out.write(writeStr.getBytes(StandardCharsets.UTF_8)));
+            assertFileContent(path, assertStr);
+        } finally {
+            Files.deleteIfExists(path);
+        }
+    }
+
+    public void writeTestFileAndAssert(Path path, OverwritePolicy overwritePolicy) throws Exception {
+        try {
+            FileUtils.safeCreate(path, overwritePolicy, out -> out.write(TEST_STRING.getBytes(StandardCharsets.UTF_8)));
+            assertFileContent(path, TEST_STRING);
+        } finally {
+            Files.deleteIfExists(path);
+        }
+    }
+
+    public static void assertFileContent(Path path, String expected) {
+        String actual;
+        try {
+            actual = Files.readString(path, StandardCharsets.UTF_8);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+        Assert.assertEquals(expected, actual);
+    }
+}