Addressed JavaDoc build failures

Also added the javadoc gradle task to the Travis CI for every commit.

.travis.yml

@@ -21,7 +21,7 @@ addons:
 install: true
 
 script:
-  - ./gradlew clean build
+  - ./gradlew clean build javadoc
 
 # required for gradle artifact caching (see https://docs.travis-ci.com/user/languages/java/#caching)
 before_cache:
@@ -46,4 +46,4 @@ deploy:
   on:
     all_branches: true
     tags: true
-    # the condition on the tag name (should be a semantic version) is inside the script, for ease of development
+    # the condition on the tag name (should be a semantic version) is inside the script, for ease of development

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/FastAvroConcurrentHashMap.java

@@ -25,9 +25,17 @@ public FastAvroConcurrentHashMap(int initialCapacity) {
    * optimization might not be ideal for the workload that most keys are unique, so be cautious
    * about the workload before adopting the FastAvroConcurrentHashMap.
    *
-   * @param key
-   * @param mappingFunction
-   * @return
+   * @param key key with which the specified value is to be associated
+   * @param mappingFunction the function to compute a value
+   * @return the current (existing or computed) value associated with
+   *         the specified key, or null if the computed value is null
+   * @throws NullPointerException if the specified key or mappingFunction
+   *         is null
+   * @throws IllegalStateException if the computation detectably
+   *         attempts a recursive update to this map that would
+   *         otherwise never complete
+   * @throws RuntimeException or Error if the mappingFunction does so,
+   *         in which case the mapping is left unestablished
    */
   @Override
   public V computeIfAbsent(K key, Function<? super K, ? extends V> mappingFunction) {

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/FastSerdeBase.java

@@ -63,7 +63,7 @@ public FastSerdeBase(String description, boolean useGenericTypes, Class defaultS
    * schema pair).
    *
    * @param prefix String to serve as a prefix for the unique name
-   * @return a unique prefix composed of the {@param prefix} appended by a unique number
+   * @return a unique prefix composed of the prefix appended by a unique number
    */
   protected String getUniqueName(String prefix) {
     String uncapitalizedPrefix = StringUtils.uncapitalize(prefix);

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/primitive/PrimitiveArrayList.java

@@ -39,15 +39,15 @@ public abstract class PrimitiveArrayList<T, L> extends AbstractList<T>
   /**
    * @param that an instance of primitive list to use for comparison
    * @param index the index of the element to compare
-   * @return the comparison result between element of this and {@param that} list at the provided {@param index}
+   * @return the comparison result between element of this and that list at the provided index
    */
   protected abstract int compareElementAtIndex(L that, int index);
 
   /**
-   * @param o instance of an Object that may or may not be a primitive list
-   * @return true if {@param o} instanceof the right type of primitive list for comparison
+   * @param object instance of an Object that may or may not be a primitive list
+   * @return true if the passed in object is an instance of the right type of primitive list for comparison
    */
-  protected abstract boolean isInstanceOfCorrectPrimitiveList(Object o);
+  protected abstract boolean isInstanceOfCorrectPrimitiveList(Object object);
 
   // Public API
 
@@ -138,12 +138,12 @@ public String toString() {
    * instance had a larger number of elements than the new one, in which case, we will reuse the array, but
    * use the {@link #size} as a boundary within the larger array.
    *
-   * @param i an index position which may or may not be within bound of the current list
-   * @throws IndexOutOfBoundsException if {@param i} is larger than the index of the last valid element
+   * @param index an index position which may or may not be within bound of the current list
+   * @throws IndexOutOfBoundsException if the index param is larger than the index of the last valid element
    */
-  protected void checkIfLargerThanSize(int i) {
-    if (i >= size) {
-      throw new IndexOutOfBoundsException("Index " + i + " out of bounds.");
+  protected void checkIfLargerThanSize(int index) {
+    if (index >= size) {
+      throw new IndexOutOfBoundsException("Index " + index + " out of bounds.");
     }
   }
 
@@ -167,7 +167,11 @@ protected void capacityCheck() {
     }
   }
 
-  /** Create an empty space in the array at the index specified by {@param location} by shifting the elements to the right */
+  /**
+   * Create an empty space in the array at the index specified by shifting the elements to the right
+   *
+   * @param location index where the element will be added
+   */
   protected void addInternal(int location) {
     if (location > size || location < 0) {
       throw new IndexOutOfBoundsException("Index " + location + " out of bounds.");

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/primitive/PrimitiveBooleanArrayList.java

@@ -85,7 +85,7 @@ protected int compareElementAtIndex(PrimitiveBooleanList that, int index) {
   }
 
   @Override
-  protected boolean isInstanceOfCorrectPrimitiveList(Object o) {
-    return o instanceof PrimitiveBooleanList;
+  protected boolean isInstanceOfCorrectPrimitiveList(Object object) {
+    return object instanceof PrimitiveBooleanList;
   }
 }

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/primitive/PrimitiveDoubleArrayList.java

@@ -86,7 +86,7 @@ protected int compareElementAtIndex(PrimitiveDoubleList that, int index) {
   }
 
   @Override
-  protected boolean isInstanceOfCorrectPrimitiveList(Object o) {
-    return o instanceof PrimitiveBooleanList;
+  protected boolean isInstanceOfCorrectPrimitiveList(Object object) {
+    return object instanceof PrimitiveBooleanList;
   }
 }

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/primitive/PrimitiveFloatArrayList.java

@@ -86,7 +86,7 @@ protected int compareElementAtIndex(PrimitiveFloatList that, int index) {
   }
 
   @Override
-  protected boolean isInstanceOfCorrectPrimitiveList(Object o) {
-    return o instanceof PrimitiveBooleanList;
+  protected boolean isInstanceOfCorrectPrimitiveList(Object object) {
+    return object instanceof PrimitiveBooleanList;
   }
 }

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/primitive/PrimitiveIntArrayList.java

@@ -86,7 +86,7 @@ protected int compareElementAtIndex(PrimitiveIntList that, int index) {
   }
 
   @Override
-  protected boolean isInstanceOfCorrectPrimitiveList(Object o) {
-    return o instanceof PrimitiveBooleanList;
+  protected boolean isInstanceOfCorrectPrimitiveList(Object object) {
+    return object instanceof PrimitiveBooleanList;
   }
 }

avro-fastserde/src/main/java/com/linkedin/avro/fastserde/primitive/PrimitiveLongArrayList.java

@@ -86,7 +86,7 @@ protected int compareElementAtIndex(PrimitiveLongList that, int index) {
   }
 
   @Override
-  protected boolean isInstanceOfCorrectPrimitiveList(Object o) {
-    return o instanceof PrimitiveBooleanList;
+  protected boolean isInstanceOfCorrectPrimitiveList(Object object) {
+    return object instanceof PrimitiveBooleanList;
   }
 }

helper/helper-common/src/main/java/com/linkedin/avroutil1/compatibility/CodeTransformations.java

@@ -252,9 +252,9 @@ public static String transformEnumClass(String code, AvroVersion minSupportedVer
    * producing uncompilable code (see see AVRO-1316). this was only fixed in avro 1.7.5+
    *
    * also - avro 1.6+ issues "new org.apache.avro.Schema.Parser().parse(...)" calls which will not compile
-   * under avro < 1.6
+   * under {@literal avro < 1.6}
    *
-   * in addition, avro < 1.6 fails to properly escape control characters in the schema string (like newlines
+   * in addition, {@literal avro < 1.6} fails to properly escape control characters in the schema string (like newlines
    * in doc properties) which will result in a json parse error when trying to instantiate the
    * generated java class (because at that point it will fail to parse the avsc in SCHEMA$)
    *

helper/helper-common/src/main/java/com/linkedin/avroutil1/compatibility/SchemaValidator.java

@@ -23,7 +23,7 @@
  * a utility class that (in combination with {@link AvroSchemaUtil#traverseSchema(Schema, SchemaVisitor)})
  * can validate avro schemas vs the avro specification. <br>
  * this class exists because historically avro has been very bad at validating its own specification
- * and this allows proper validation under older (<1.9) versions of avro
+ * and this allows proper validation under versions of {@literal avro < 1.9}
  */
 public class SchemaValidator implements SchemaVisitor {
   private final static Set<Schema.Type> NAMED_TYPES = Collections.unmodifiableSet(new HashSet<>(Arrays.asList(