Added improved exception handling of isValidMapcodeFormat

Author: rijnb

README.md

@@ -480,6 +480,10 @@ Normally, one of our developers should be able to comment on them and fix.
 mat
 These are the release notes for the Java library for mapcodes.
 
+### 2.4.12
+
+* Added unit tests to check internal data structures.
+
 ### 2.4.11
 
 * Fixed a bug in `Mapcode.isValidMapcodeFormat()` which caused an exception when parsing a Unicode mapcode

pom.xml

@@ -8,7 +8,7 @@
     <artifactId>mapcode</artifactId>
 
     <packaging>jar</packaging>
-    <version>2.4.11</version>
+    <version>2.4.12</version>
 
     <name>Mapcode Java Library</name>
     <description>

src/main/java/com/mapcode/Decoder.java

@@ -205,7 +205,7 @@ static MapcodeZone decodeToMapcodeZone(@Nonnull final String argMapcode,
     // Private methods.
     // ----------------------------------------------------------------------
 
-    private final static int[] DECODE_CHARS = {
+    final static int[] DECODE_CHARS = {
             -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
             -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
             -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
@@ -224,7 +224,7 @@ static MapcodeZone decodeToMapcodeZone(@Nonnull final String argMapcode,
             -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
     };
 
-    private static class Unicode2Ascii {
+    static class Unicode2Ascii {
 
         final char min;
         final char max;
@@ -245,7 +245,7 @@ private static class Unicode2Ascii {
     private static final char MISSCODE = '?';
 
     // @formatter:off
-    @SuppressWarnings("LongLine") private final static char[][] ASCII2LANGUAGE = {
+    @SuppressWarnings("LongLine") final static char[][] ASCII2LANGUAGE = {
             // Character:   A         B         C         D         E         F         G         H         I         J        K          L         M         N         O         P         Q         R         S         T         U         V         W         X         Y         Z         0         1         2         3         4         5         6         7         8         9
             /* Roman    */ {'\u0041', '\u0042', '\u0043', '\u0044', '\u0045', '\u0046', '\u0047', '\u0048', '\u0049', '\u004a', '\u004b', '\u004c', '\u004d', '\u004e', '\u004f', '\u0050', '\u0051', '\u0052', '\u0053', '\u0054', '\u0055', '\u0056', '\u0057', '\u0058', '\u0059', '\u005a', '\u0030', '\u0031', '\u0032', '\u0033', '\u0034', '\u0035', '\u0036', '\u0037', '\u0038', '\u0039'}, // Roman
             /* Greek    */ {'\u0391', '\u0392', '\u039e', '\u0394', '\u0388', '\u0395', '\u0393', '\u0397', '\u0399', '\u03a0', '\u039a', '\u039b', '\u039c', '\u039d', '\u039f', '\u03a1', '\u0398', '\u03a8', '\u03a3', '\u03a4', '\u0389', '\u03a6', '\u03a9', '\u03a7', '\u03a5', '\u0396', '\u0030', '\u0031', '\u0032', '\u0033', '\u0034', '\u0035', '\u0036', '\u0037', '\u0038', '\u0039'}, // Greek
@@ -279,7 +279,7 @@ private static class Unicode2Ascii {
     // @formatter:on
 
     // @formatter:off
-    @SuppressWarnings("LongLine") private final static Unicode2Ascii[] UNICODE2ASCII = {
+    @SuppressWarnings("LongLine") final static Unicode2Ascii[] UNICODE2ASCII = {
             /* Roman    */ new Unicode2Ascii('\u0041', '\u005a', "ABCDEFGHIJKLMNOPQRSTUVWXYZ"),                                                        // Roman
             /* Greek    */ new Unicode2Ascii('\u0388', '\u03a9', "EU???????ABGDFZHQIKLMNCOJP?STYVXRW"),                                                // Greek
             /* Cyrillic */ new Unicode2Ascii('\u0410', '\u042f', "AZBGDEFNI?KLMHOJPCTYQXSVW????U?R"),                                                  // Cyrillic
@@ -728,7 +728,7 @@ static String decodeUTF16(@Nonnull final String mapcode) {
         if (mapcode.startsWith(String.valueOf(GREEK_CAPITAL_ALPHA))) {
             final String unpacked = aeuUnpack(result);
             if (unpacked.isEmpty()) {
-                throw new AssertionError("decodeUTF16: cannot decode " + mapcode);
+                throw new UnknownDecodeException("decodeUTF16: cannot decode " + mapcode);
             }
             result = Encoder.aeuPack(unpacked, false);
         }

src/main/java/com/mapcode/Mapcode.java

@@ -322,6 +322,8 @@ public static boolean isValidMapcodeFormat(@Nullable final String mapcode) throw
             return true;
         } catch (final UnknownPrecisionFormatException ignored) {
             return false;
+        } catch (final UnknownDecodeException ignored2) {
+            return false;
         }
     }
 

src/main/java/com/mapcode/UnknownDecodeException.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2014-2019, Stichting Mapcode Foundation (http://www.mapcode.com)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.mapcode;
+
+import javax.annotation.Nonnull;
+
+/**
+ * This runtime exception is thrown is decoding fails for an unknown reason.
+ * The exception is not exposed externally.
+ */
+final class UnknownDecodeException extends IllegalStateException {
+    private static final long serialVersionUID = 1L;
+
+    UnknownDecodeException(@Nonnull final String message) {
+        super(message);
+        assert message != null;
+    }
+}

src/test/java/com/mapcode/DecoderTest.java

@@ -16,6 +16,7 @@
 
 package com.mapcode;
 
+import com.mapcode.Decoder.Unicode2Ascii;
 import org.junit.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -26,9 +27,36 @@
 public class DecoderTest {
     private static final Logger LOG = LoggerFactory.getLogger(DecoderTest.class);
 
+    @Test
+    public void tableDecodeChars() {
+        LOG.info("tableDecodeChars");
+        assertEquals("Length: " + Decoder.DECODE_CHARS.length, 256, Decoder.DECODE_CHARS.length);
+    }
+
+    @Test
+    public void tableAscii2Language() {
+        LOG.info("tableAscii2Language");
+        assertEquals(Decoder.ASCII2LANGUAGE.length, Decoder.UNICODE2ASCII.length - 10 /* Digits */ - 3 /* Lowercase */);
+        int i = 1;
+        for (char[] chars : Decoder.ASCII2LANGUAGE) {
+            assertEquals("At row " + i + ", length: " + chars.length, 36, chars.length);
+            ++i;
+        }
+    }
+
+    @Test
+    public void tableUnicodeToAscii() {
+        LOG.info("tableUnicodeToAscii");
+        for (Unicode2Ascii unicode2Ascii : Decoder.UNICODE2ASCII) {
+            assertEquals("Error at: u" + Integer.toHexString(unicode2Ascii.min),
+                    (int) unicode2Ascii.max - (int) unicode2Ascii.min, unicode2Ascii.convert.length() - 1);
+        }
+    }
+
     @SuppressWarnings("JUnitTestMethodWithNoAssertions")
     @Test
     public void getInternationalGrid() {
+        LOG.info("getInternationalGrid");
         final DataModel dataModel = DataModel.getInstance();
         final int world = Territory.AAA.getNumber();
         final int to = dataModel.getDataLastRecord(world);