[MPLUGIN-521] Nested types not properly extracted cause exception while generating Javadoc URLs

This closes #281

Author: michael-o

maven-plugin-tools-generators/src/main/java/org/apache/maven/tools/plugin/generator/PluginDescriptorFilesGenerator.java

@@ -625,7 +625,7 @@ protected void writeParameterType(
         }
     }
 
-    static URI getJavadocUrlForType(JavadocLinkGenerator javadocLinkGenerator, String type) {
+    private static String extractBinaryNameForJavadoc(String type) {
         final String binaryName;
         int startOfParameterType = type.indexOf("<");
         if (startOfParameterType != -1) {
@@ -637,10 +637,10 @@ static URI getJavadocUrlForType(JavadocLinkGenerator javadocLinkGenerator, Strin
                     .split(",\\s*");
             switch (parameterTypes.length) {
                 case 1: // if only one parameter type, assume collection, first parameter type is most interesting
-                    binaryName = parameterTypes[0];
+                    binaryName = extractBinaryNameForJavadoc(parameterTypes[0]);
                     break;
                 case 2: // if two parameter types assume map, second parameter type is most interesting
-                    binaryName = parameterTypes[1];
+                    binaryName = extractBinaryNameForJavadoc(parameterTypes[1]);
                     break;
                 default:
                     // all other cases link to main type
@@ -649,7 +649,11 @@ static URI getJavadocUrlForType(JavadocLinkGenerator javadocLinkGenerator, Strin
         } else {
             binaryName = type;
         }
-        return javadocLinkGenerator.createLink(binaryName);
+        return binaryName;
+    }
+
+    static URI getJavadocUrlForType(JavadocLinkGenerator javadocLinkGenerator, String type) {
+        return javadocLinkGenerator.createLink(extractBinaryNameForJavadoc(type));
     }
 
     /**

maven-plugin-tools-generators/src/test/java/org/apache/maven/tools/plugin/generator/PluginDescriptorFilesGeneratorTest.java

@@ -164,6 +164,10 @@ void testGetJavadocUrlForType() throws URISyntaxException {
                 javadocBaseUri.resolve("java/lang/Integer.html"),
                 PluginDescriptorFilesGenerator.getJavadocUrlForType(
                         linkGenerator, "java.lang.Map<java.lang.String,java.lang.Integer>"));
+        assertEquals(
+                javadocBaseUri.resolve("java/lang/Integer.html"),
+                PluginDescriptorFilesGenerator.getJavadocUrlForType(
+                        linkGenerator, "java.lang.Map<java.lang.String,java.util.List<java.lang.Integer>>"));
         assertEquals(
                 javadocBaseUri.resolve("java/util/function/BiFunction.html"),
                 PluginDescriptorFilesGenerator.getJavadocUrlForType(