NEW PR

core-java-modules/core-java-datetime-string-2/pom.xml

@@ -13,6 +13,14 @@
         <version>0.0.1-SNAPSHOT</version>
     </parent>
 
+    <dependencies>
+        <dependency>
+            <groupId>joda-time</groupId>
+            <artifactId>joda-time</artifactId>
+            <version>${joda-time.version}</version>
+        </dependency>
+    </dependencies>
+
     <build>
         <plugins>
             <plugin>
@@ -22,4 +30,8 @@
         </plugins>
     </build>
 
+    <properties>
+        <joda-time.version>2.12.5</joda-time.version>
+    </properties>
+
 </project>

core-java-modules/core-java-datetime-string-2/src/test/java/com/baeldung/timestamp/CurrentTimeAsFileNameUnitTest.java

@@ -0,0 +1,114 @@
+package com.baeldung.timestamp;
+
+import static org.junit.Assert.assertTrue;
+
+import java.text.MessageFormat;
+import java.text.SimpleDateFormat;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.time.OffsetDateTime;
+import java.time.ZoneId;
+import java.time.ZoneOffset;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoUnit;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.regex.Pattern;
+
+import org.joda.time.DateTime;
+import org.joda.time.format.DateTimeFormat;
+import org.junit.Test;
+
+public class CurrentTimeAsFileNameUnitTest {
+
+    static final String TIMESTAMP_FORMAT = "yyyyMMddHHmmss";
+    static final DateTimeFormatter DATETIME_FORMATTER = DateTimeFormatter.ofPattern(TIMESTAMP_FORMAT);
+    static final SimpleDateFormat SIMPLEDATE_FORMAT = new SimpleDateFormat(TIMESTAMP_FORMAT);
+
+    @Test
+    public void whenUsingCalendar_thenCurrentTimeAsFileName() {
+        String currentTime = SIMPLEDATE_FORMAT.format(Calendar.getInstance().getTime());
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    @Test
+    public void whenUsingDate_thenCurrentTimeAsFileName() {
+        String currentTime = SIMPLEDATE_FORMAT.format(new Date());
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    @Test
+    public void whenUsingInstant_thenCurrentTimeAsFileName() {
+        String currentTime = Instant
+            .now()
+            .truncatedTo(ChronoUnit.SECONDS)
+            .toString()
+            .replaceAll("[:TZ-]", "");
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    @Test
+    public void whenUsingLocalDateTime_thenCurrentTimeAsFileName() {
+        String currentTime = LocalDateTime.now().format(DATETIME_FORMATTER);
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    @Test
+    public void whenUsingZonedDateTime_thenCurrentTimeAsFileName() {
+        String currentTime = ZonedDateTime
+            .now(ZoneId.of("Europe/Paris"))
+            .format(DATETIME_FORMATTER);
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    @Test
+    public void whenUsingOffsetDateTime_thenCurrentTimeAsFileName() {
+        String currentTime = OffsetDateTime
+            .of(LocalDateTime.now(), ZoneOffset.of("+01:00"))
+            .format(DATETIME_FORMATTER);
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    @Test
+    public void whenUsingJodaDateTime_thenCurrentTimeAsFileName() {
+        String currentTime = DateTime.now().toString(TIMESTAMP_FORMAT);
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    @Test
+    public void whenUsingJodaInstant_thenCurrentTimeAsFileName() {
+        String currentTime = DateTimeFormat
+            .forPattern(TIMESTAMP_FORMAT)
+            .print(org.joda.time.Instant.now()
+                .toDateTime());
+        String fileName = getFileName(currentTime);
+
+        assertTrue(verifyFileName(fileName));
+    }
+
+    String getFileName(String currentTime) {
+        return MessageFormat.format("{0}.txt", currentTime);
+    }
+
+    boolean verifyFileName(String fileName) {
+        return Pattern
+            .compile("[0-9]{14}+\\.txt", Pattern.CASE_INSENSITIVE)
+            .matcher(fileName)
+            .matches();
+    }
+}