Add description for encodings and encoding list

CHANGELOG

@@ -4,6 +4,7 @@
 * add proguard
 * add column output
 * add url encode flag
+* add list of encodings
 
 ## v0.2.0
 * add external seeding with random.org

src/main/java/at/favre/tools/dice/RndTool.java

@@ -2,7 +2,7 @@
 
 import at.favre.tools.dice.encode.Base32Encoder;
 import at.favre.tools.dice.encode.Encoder;
-import at.favre.tools.dice.encode.Loader;
+import at.favre.tools.dice.encode.EncoderHandler;
 import at.favre.tools.dice.service.RandomOrgServiceHandler;
 import at.favre.tools.dice.ui.Arg;
 import at.favre.tools.dice.ui.CLIParser;
@@ -13,7 +13,6 @@
 import java.nio.charset.StandardCharsets;
 import java.security.SecureRandom;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 
 public class RndTool {
@@ -29,8 +28,16 @@ public static void main(String[] args) {
     }
 
     static boolean execute(Arg arguments) {
-        Loader loader = new Loader();
-        List<Encoder> encoders = loader.load();
+        EncoderHandler loader = new EncoderHandler();
+        loader.load();
+
+        Encoder encoder = loader.findByName(arguments.encoding);
+
+        if (encoder == null) {
+            System.err.println("Given encoder '" + arguments.encoding + "' is not available.");
+            System.err.println("\nAvailable encoders:\n\n" + loader.returnRegistryInfo());
+            System.exit(2);
+        }
 
         SecureRandom secureRandom = new SecureRandom();
         if (arguments.urlencode) {
@@ -58,14 +65,8 @@ static boolean execute(Arg arguments) {
 
         System.out.println();
 
-        for (Encoder encoder : encoders) {
-            if (Arrays.asList(encoder.names()).contains(arguments.encoding)) {
-                printRandoms(arguments, encoder, secureRandom);
-                return true;
-            }
-        }
-
-        return false;
+        printRandoms(arguments, encoder, secureRandom);
+        return true;
     }
 
     private static void printRandoms(Arg arguments, Encoder encoder, SecureRandom secureRandom) {

src/main/java/at/favre/tools/dice/encode/AByteEncoder.java

@@ -0,0 +1,8 @@
+package at.favre.tools.dice.encode;
+
+abstract class AByteEncoder implements Encoder {
+    @Override
+    public String getDescription() {
+        return "<TODO>";
+    }
+}

src/main/java/at/favre/tools/dice/encode/AEncoder.java

@@ -1,8 +1,8 @@
 package at.favre.tools.dice.encode;
 
-public abstract class AEncoder implements Encoder {
+abstract class AEncoder implements Encoder {
 
-    public String encodeInternal(byte[] array, String prefix, String postfix, String sep, ByteEncoder byteEncoder) {
+    String encodeInternal(byte[] array, String prefix, String postfix, String sep, ByteEncoder byteEncoder) {
         StringBuilder sb = new StringBuilder(prefix);
         for (int i = 0; i < array.length; i++) {
             sb.append(byteEncoder.encodeByte(array[i])).append(sep).append(" ");
@@ -12,6 +12,11 @@ public String encodeInternal(byte[] array, String prefix, String postfix, String
         return sb.toString();
     }
 
+    @Override
+    public String getDescription() {
+        return "<TODO>";
+    }
+
     interface ByteEncoder {
         String encodeByte(byte b);
     }

src/main/java/at/favre/tools/dice/encode/AlphabetEncoder.java

@@ -19,4 +19,9 @@ public String encode(byte[] array) {
         }
         return sb.toString();
     }
+
+    @Override
+    public String getDescription() {
+        return "<TODO>";
+    }
 }

src/main/java/at/favre/tools/dice/encode/Ascii85Encoder.java

@@ -7,7 +7,7 @@
  *
  * See https://github.com/fzakaria/ascii85
  */
-public class Ascii85Encoder implements Encoder {
+public class Ascii85Encoder extends AByteEncoder {
 
     @Override
     public String encode(byte[] array) {

src/main/java/at/favre/tools/dice/encode/Base16Encoder.java

@@ -6,7 +6,7 @@
 /**
  * Encodes in to base16 (ie. hex) e.g. <code>6e33a8f4c9f69e91</code>
  */
-public class Base16Encoder implements Encoder {
+public class Base16Encoder extends AByteEncoder {
     private boolean lowerCase;
 
     public Base16Encoder() {
@@ -26,4 +26,9 @@ public String encode(byte[] array) {
     public String[] names() {
         return new String[]{"base16", Arg.DEFAULT_ENCODING};
     }
+
+    @Override
+    public String getDescription() {
+        return "Hex or Base16 encoding (lowercase) e.g 6e33a8f4c";
+    }
 }

src/main/java/at/favre/tools/dice/encode/Base32Encoder.java

@@ -5,7 +5,7 @@
 /**
  * Encodes in to base32 e.g. <code>NHSMJ5VH6P5QRAT4EXAP2BDZ5Q</code>
  */
-public class Base32Encoder implements Encoder {
+public class Base32Encoder extends AByteEncoder {
 
     @Override
     public String encode(byte[] array) {
@@ -16,4 +16,9 @@ public String encode(byte[] array) {
     public String[] names() {
         return new String[]{"base32"};
     }
+
+    @Override
+    public String getDescription() {
+        return "Base32 encoding without padding e.g NHSMJ5VH6P5QRAT4EXAP2BDZ5Q";
+    }
 }

src/main/java/at/favre/tools/dice/encode/Base64Encoder.java

@@ -5,7 +5,7 @@
 /**
  * Encodes in to base64 e.g. <code>NUZDT6c7SOxz0YgRw3JGqc+BKnJM3fuH</code>
  */
-public class Base64Encoder implements Encoder {
+public class Base64Encoder extends AByteEncoder {
 
     @Override
     public String encode(byte[] array) {
@@ -16,4 +16,9 @@ public String encode(byte[] array) {
     public String[] names() {
         return new String[]{"base64"};
     }
+
+    @Override
+    public String getDescription() {
+        return "Base64 encoding without padding e.g NUZDT6c7SOxz0YgRw3JGqc+BKnJM3fuH";
+    }
 }

src/main/java/at/favre/tools/dice/encode/BinaryEncoder.java

@@ -7,7 +7,7 @@
 /**
  * Encodes in to binary representation e.g. <code>010010011</code>
  */
-public class BinaryEncoder implements Encoder {
+public class BinaryEncoder extends AByteEncoder {
 
     private final static int GROUP_LENGTH = 8;
 
@@ -29,4 +29,9 @@ public String encode(byte[] array) {
     public String[] names() {
         return new String[]{"binary", "base2", "bin", "bit"};
     }
+
+    @Override
+    public String getDescription() {
+        return "Binary encoding in 8 bit groups e.g 010010011 110000011";
+    }
 }

src/main/java/at/favre/tools/dice/encode/DecimalByteEncoder.java

@@ -5,7 +5,7 @@
 /**
  * Encodes every byte as a decimal
  */
-public class DecimalByteEncoder implements Encoder {
+public class DecimalByteEncoder extends AByteEncoder {
 
     @Override
     public String encode(byte[] array) {

src/main/java/at/favre/tools/dice/encode/Encoder.java

@@ -1,7 +1,22 @@
 package at.favre.tools.dice.encode;
 
+/**
+ * Interface for encoding byte arrays to string
+ */
 public interface Encoder {
     String encode(byte[] array);
 
+    /**
+     * The names or alias for a user select the encoder
+     *
+     * @return all available names
+     */
     String[] names();
+
+    /**
+     * User readable description what this encoder does
+     *
+     * @return description
+     */
+    String getDescription();
 }

src/main/java/at/favre/tools/dice/encode/Loader.java → src/main/java/at/favre/tools/dice/encode/EncoderHandler.java

@@ -2,7 +2,7 @@
 
 import java.util.*;
 
-public class Loader {
+public class EncoderHandler {
 
     public static final List<Encoder> ENCODERS = Collections.unmodifiableList(Arrays.asList(
             new AlphaNumericEncoder(),
@@ -38,4 +38,28 @@ public List<Encoder> load() {
 
         return ENCODERS;
     }
+
+    public Encoder findByName(String name) {
+        if (name != null) {
+            for (Encoder encoder : ENCODERS) {
+                if (Arrays.asList(encoder.names()).contains(name)) {
+                    return encoder;
+                }
+            }
+        }
+        return null;
+    }
+
+    public String returnRegistryInfo() {
+        StringBuilder sb = new StringBuilder();
+
+        for (Encoder encoder : ENCODERS) {
+            for (String name : encoder.names()) {
+                sb.append(name).append(", ");
+            }
+            sb.delete(sb.length() - 2, sb.length()).append("\n");
+            sb.append("\tDescription: ").append(encoder.getDescription()).append("\n");
+        }
+        return sb.toString();
+    }
 }

src/main/java/at/favre/tools/dice/ui/CLIParser.java

@@ -1,5 +1,6 @@
 package at.favre.tools.dice.ui;
 
+import at.favre.tools.dice.encode.EncoderHandler;
 import at.favre.tools.dice.util.CmdUtil;
 import org.apache.commons.cli.*;
 
@@ -76,7 +77,7 @@ private static Options setupOptions() {
         Options options = new Options();
 
         Option count = Option.builder(ARG_COUNT).longOpt("count").argName("number").desc("How many randoms should be generated").hasArgs().build();
-        Option encodeing = Option.builder(ARG_ENCODING).longOpt("encoding").argName("string").hasArgs().desc("What output encode should be used").build();
+        Option encodeing = Option.builder(ARG_ENCODING).longOpt("encoding").argName("string").hasArgs().desc("What output encode should be used. Available encodings include:\n" + new EncoderHandler().returnRegistryInfo()).build();
         Option seed = Option.builder(ARG_SEED).longOpt("seed").argName("string").hasArgs().desc("Uses the utf-8 byte representation to seed the SecureRandom.").build();
         Option debugOpt = Option.builder(ARG_DEBUG).longOpt("debug").hasArg(false).desc("Prints additional info for debugging.").build();
         Option onlineOpt = Option.builder(ARG_ONLINE).longOpt("offline").hasArg(false).desc("Skips request to Random.org to seed random generator (use when offline).").build();

src/test/java/at/favre/tools/dice/encode/LoaderTest.java → src/test/java/at/favre/tools/dice/encode/EncoderHandlerTest.java

@@ -8,10 +8,10 @@
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 
-public class LoaderTest {
+public class EncoderHandlerTest {
     @Test
     public void load() throws Exception {
-        List<Encoder> encoders = new Loader().load();
+        List<Encoder> encoders = new EncoderHandler().load();
 
         System.out.println(Arrays.toString(encoders.toArray()));