Modify numbering to four digits #2

S00_BoringMain.java → S0000_BoringMain.java

@@ -1,4 +1,4 @@
-public class S00_BoringMain {
+public class S0000_BoringMain {
 
     public static void main(String[] args) {
         System.out.println("boring and complex");

S01_Executable.java → S0001_Executable.java

@@ -1,4 +1,4 @@
-public interface S01_Executable {
+public interface S0001_Executable {
 
     static void main(String... args) {
         System.out.println("hello,duke");

S02_MainInterface.java → S0002_MainInterface.java

@@ -1,4 +1,4 @@
-interface S02_MainInterface {
+interface S0002_MainInterface {
 
     static void main(String... args) {
         System.out.println("hello,duke");

S0003_VarArgs.java

@@ -0,0 +1,14 @@
+interface S0003_VarArgs {
+
+  static void hello(String... messages) {
+    for (var message : messages) {
+      System.out.println(message);
+    }
+  }
+
+  static void main(String... args) {
+    S0003_VarArgs.hello("hey", "duke", "java");
+    S0003_VarArgs.hello("is", "working");
+    S0003_VarArgs.hello(new String[] { "is", "always", "working" });
+  }
+}

S04_Timer.java → S0004_Timer.java

@@ -1,7 +1,7 @@
 import java.util.Timer;
 import java.util.TimerTask;
 
-public class S04_Timer {
+public class S0004_Timer {
     public static void main(String[] args) {
         var task = new TimerTask() {
 

S05_ScheduledThreadPool.java → S0005_ScheduledThreadPool.java

@@ -1,11 +1,11 @@
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 
-interface S05_ScheduledThreadPool {
+interface S0005_ScheduledThreadPool {
 
   static void main(String... args) {
     var scheduler = Executors.newScheduledThreadPool(1);
     scheduler
-    .scheduleAtFixedRate(()-> System.out.println("hello"), 0, 1, TimeUnit.SECONDS);
+        .scheduleAtFixedRate(() -> System.out.println("hello"), 0, 1, TimeUnit.SECONDS);
   }
 }

S06_FileWatch.java → S0006_FileWatch.java

@@ -3,7 +3,7 @@
 import java.nio.file.StandardWatchEventKinds;
 import java.nio.file.WatchEvent;
 
-interface S06_FileWatch {
+interface S0006_FileWatch {
 
   static void main(String... args) throws Exception {
 

S07_FileDiff.java → S0007_FileDiff.java

@@ -2,11 +2,11 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 
-interface S07_FileDiff {
+interface S0007_FileDiff {
 
   static void main(String... args) throws IOException {
-    var first = Path.of("a.txt");
-    var second = Path.of("b.txt");
+    var first = Path.of("S0000_BoringMain.java");
+    var second = Path.of("S0001_Executable.java");
 
     var firstDifferentByte = Files.mismatch(first, second);
     System.out.println(firstDifferentByte);

S08_CopyToClipboard.java → S0008_CopyToClipboard.java

@@ -4,7 +4,7 @@
 import java.awt.datatransfer.UnsupportedFlavorException;
 import java.io.IOException;
 
-public class S08_CopyToClipboard {
+public class S0008_CopyToClipboard {
 
     public static void main(String[] args) {
         var message = "from java " + System.nanoTime();

S09_ReadFromClipboard.java → S0009_ReadFromClipboard.java

@@ -3,7 +3,7 @@
 import java.awt.datatransfer.UnsupportedFlavorException;
 import java.io.IOException;
 
-public class S09_ReadFromClipboard {
+public class S0009_ReadFromClipboard {
 
     public static void main(String[] args) throws UnsupportedFlavorException, IOException {
         var cb = Toolkit.getDefaultToolkit().getSystemClipboard();

S10_ReadFromConsole.java → S0010_ReadFromConsole.java

@@ -1,4 +1,4 @@
-public class S10_ReadFromConsole {
+public class S0010_ReadFromConsole {
 
     public static void main(String[] args) {
         var console = System.console();

S11_ReadPassword.java → S0011_ReadPassword.java

@@ -1,4 +1,4 @@
-public class S11_ReadPassword {
+public class S0011_ReadPassword {
 
     public static void main(String[] args) {
         var console = System.console();

S12_CustomJVM.java → S0012_CustomJVM.java

@@ -1,4 +1,4 @@
-public interface S12_CustomJVM {
+public interface S0012_CustomJVM {
 
     /**
      * javac

S13_Emoji.java → S0013_Emoji.java

@@ -1,4 +1,5 @@
-public class S13_Emoji {
+public class S0013_Emoji {
+
     static final String ROCKET = "🚀";
 
     public static void main(String[] args) {

S14_SystemOutInColor.java → S0014_SystemOutInColor.java

@@ -2,7 +2,7 @@
 /**
  * https://en.wikipedia.org/wiki/ANSI_escape_code
  */
-interface S14_SystemOutInColor {
+interface S0014_SystemOutInColor {
 
     static void main(String... args) {
         System.out.println("\033[0;31mhello, duke");

S15_BuiltInLogger.java → S0015_BuiltInLogger.java

@@ -1,6 +1,6 @@
 import java.lang.System.Logger.Level;
 
-public class S15_BuiltInLogger {
+public class S0015_BuiltInLogger {
     public static void main(String[] args) {
         var log = System.getLogger("duke");
         log.log(Level.INFO, "hello, world");

S16_AutoCloseable.java → S0016_AutoCloseable.java

@@ -1,11 +1,11 @@
-public class S16_AutoCloseable implements AutoCloseable {
+public class S0016_AutoCloseable implements AutoCloseable {
     @Override
     public void close() {
         System.out.println("closing");
     }
 
     public static void main(String[] args) {
-        try (var a = new S16_AutoCloseable()) {
+        try (var a = new S0016_AutoCloseable()) {
         }
     }
 

S17_StaticInitializer.java → S0017_StaticInitializer.java

@@ -1,4 +1,4 @@
-class S17_StaticInitializer{
+class S0017_StaticInitializer{
     static{
         System.out.println("s1");
     }

S0018_InitializersAndConstructors.java

@@ -0,0 +1,20 @@
+public class S0018_InitializersAndConstructors {
+
+    public S0018_InitializersAndConstructors() {
+        System.out.println("parameterless");
+    }
+
+    public S0018_InitializersAndConstructors(String name) {
+        System.out.println(name);
+    }
+
+    {
+        System.out.println("shared code");
+    }
+
+
+    public static void main(String[] args) {
+        new S0018_InitializersAndConstructors();
+        new S0018_InitializersAndConstructors("with parameter");
+    }
+}

S20_Assert.java → S0020_Assert.java

@@ -1,7 +1,7 @@
 import java.util.Objects;
 
 //-ea
-public class S20_Assert {
+public class S0020_Assert {
 
     static void parameterNeeded(String input) {
         assert input != null;

S21_TerminalReset.java → S0021_TerminalReset.java

@@ -1,6 +1,6 @@
 import java.io.IOException;
 
-interface S21_TerminalReset {
+interface S0021_TerminalReset {
 
   static void main(String... args) throws IOException {
     System.out.println("duke is not nice");

S22_CompactNumberFormat.java → S0022_CompactNumberFormat.java

@@ -1,6 +1,6 @@
 import java.text.NumberFormat;
 
-public class S22_CompactNumberFormat {
+public class S0022_CompactNumberFormat {
 
     public static void main(String[] args) {
         var number = 10000;

S23_UnderscoresInNumbers.java → S0023_UnderscoresInNumbers.java

@@ -1,4 +1,4 @@
-public class S23_UnderscoresInNumbers {
+public class S0023_UnderscoresInNumbers {
 
     public static void main(String[] args) {
         var number = 10_000_000;

S24_FunctionalInterface.java → S0024_FunctionalInterface.java

@@ -1,5 +1,5 @@
 
 @FunctionalInterface
-interface S24_FunctionalInterface {
+interface S0024_FunctionalInterface {
     void first();
 }

S25_Sam.java → S0025_Sam.java

@@ -1,4 +1,4 @@
-public class S25_Sam {
+public class S0025_Sam {
     public static void main(String[] args) {
         Runnable r = () -> System.out.println("working");
         new Thread(r).start();

S26_AttributeDefaultOptional.java → S0026_AttributeDefaultOptional.java

@@ -1,6 +1,6 @@
 import static java.util.Optional.ofNullable;
 
-interface S26_AttributeDefaultOptional {
+interface S0026_AttributeDefaultOptional {
 
   class Developer {
     private String name;

S27_ObjectsPreconditions.java → S0027_ObjectsPreconditions.java

@@ -1,14 +1,14 @@
 import java.time.LocalDateTime;
 import java.util.Objects;
 
-public class S27_ObjectsPreconditions {
+public class S0027_ObjectsPreconditions {
 
     static String error() {
         return "input please now: " + LocalDateTime.now();
     }
 
     static void parameterPlease(String input) {
-        Objects.requireNonNull(input, S27_ObjectsPreconditions::error);
+        Objects.requireNonNull(input, S0027_ObjectsPreconditions::error);
     }
 
     public static void main(String[] args) {

S28_Formatted.java → S0028_Formatted.java

@@ -1,4 +1,4 @@
-public class S28_Formatted {
+public class S0028_Formatted {
 
     public static void main(String[] args) {
         var message = """

S29_PositionInFormatted.java → S0029_PositionInFormatted.java

@@ -1,4 +1,4 @@
-public class S29_PositionInFormatted {
+public class S0029_PositionInFormatted {
 
     public static void main(String[] args) {
         var message = """

S30_CreateTempFolder.java → S0030_CreateTempFolder.java

@@ -1,7 +1,7 @@
 import java.io.IOException;
 import java.nio.file.Files;
 
-public class S30_CreateTempFolder {
+public class S0030_CreateTempFolder {
 
     public static void main(String[] args) throws IOException {
         var temp = Files.createTempDirectory("airhacks");

S31_CreateDirectories.java → S0031_CreateDirectories.java

@@ -2,7 +2,7 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 
-public class S31_CreateDirectories {
+public class S0031_CreateDirectories {
 
     public static void main(String[] args) throws IOException {
         var path = Path.of("hello/duke/rocks");

S32_DirectoryStream.java → S0032_DirectoryStream.java

@@ -2,7 +2,7 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 
-public class S32_DirectoryStream {
+public class S0032_DirectoryStream {
 
     static void createDirectories() throws IOException {
         for (int i = 0; i < 10; i++) {

S33_Capitalize.java → S0033_Capitalize.java

@@ -1,4 +1,4 @@
-interface S33_Capitalize {
+interface S0033_Capitalize {
   static String cap(String name) {
     var first = Character.toUpperCase(name.charAt(0));
     var rem = name.substring(1);

S34_CloudNativeSystemEnv.java → S0034_CloudNativeSystemEnv.java

@@ -1,4 +1,4 @@
-public class S34_CloudNativeSystemEnv {
+public class S0034_CloudNativeSystemEnv {
 
     public static void main(String[] args) {
         var home = System.getenv().get("JAVA_HOME");

S35_LinesString.java → S0035_LinesString.java

@@ -1,4 +1,4 @@
-public class S35_LinesString {
+public class S0035_LinesString {
 
     public static void main(String[] args) {
         var result = """

S37_FileCopy.java → S0037_FileCopy.java

@@ -2,7 +2,7 @@
 import static java.nio.file.Path.*;
 import java.io.IOException;
 
-interface S37_FileCopy {
+interface S0037_FileCopy {
   static void main(String... args) throws IOException {
     Files.copy(of("App.java"), of("App.next"));
   }

S38_StreamArraytoStream.java → S0038_StreamArraytoStream.java

@@ -1,7 +1,7 @@
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
-public class S38_StreamArraytoStream {
+public class S0038_StreamArraytoStream {
 
     public static void main(String[] args) {
         var stringArgs = Stream

S39_EndlessStreams.java → S0039_EndlessStreams.java

@@ -1,7 +1,7 @@
 import java.time.LocalDateTime;
 import java.util.stream.Stream;
 
-interface S39_EndlessStreams {
+interface S0039_EndlessStreams {
 
   static void main(String... args) {
     var dates = Stream

S40_SoutRedirect.java → S0040_SoutRedirect.java

@@ -4,7 +4,7 @@
 /**
  * App
  */
-public class S40_SoutRedirect {
+public class S0040_SoutRedirect {
 
     public static void main(String[] args) throws FileNotFoundException {
         var s = new PrintStream("log.file");

S41_TimeVsChronoUnit.java → S0041_TimeVsChronoUnit.java

@@ -1,7 +1,7 @@
 import java.time.temporal.ChronoUnit;
 import java.util.concurrent.TimeUnit;
 
-interface S41_TimeVsChronoUnit {
+interface S0041_TimeVsChronoUnit {
 
   static void main(String... args) throws InterruptedException {
     System.out.println("what's the difference?");

S42_IntegerCaching.java → S0042_IntegerCaching.java

@@ -1,4 +1,4 @@
-interface S42_IntegerCaching {
+interface S0042_IntegerCaching {
 
   static void main(String... args) {
     var number = 128;

S43_JWTDecoder.java → S0043_JWTDecoder.java

@@ -2,7 +2,7 @@
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
-interface S43_JWTDecoder {
+interface S0043_JWTDecoder {
 
   static void main(String... args) {
     var parts = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"

S44_Ternary.java → S0044_Ternary.java

@@ -1,4 +1,4 @@
-interface S44_Ternary {
+interface S0044_Ternary {
 
   static void main(String... args) {
     var input = "";

S45_Peek.java → S0045_Peek.java

@@ -1,6 +1,6 @@
 import java.util.List;
 
-public class S45_Peek {
+public class S0045_Peek {
   public static void main(String[] args) {
     var result = List.of("a", "b", "c")
         .stream()

S50_CrazyQuestion.java → S0050_CrazyQuestion.java

@@ -1,4 +1,4 @@
-interface S50_CrazyQuestion {
+interface S0050_CrazyQuestion {
 
   static void main(String... args) {
 

S51_Frequency.java → S0051_Frequency.java

@@ -1,7 +1,7 @@
 import java.util.Collections;
 import java.util.List;
 
-interface S51_Frequency {
+interface S0051_Frequency {
 
   static void main(String... args) {
     var numbers = List.of(1,2,2,2,3,3,3);