Summary

Add explicit constructors to two classes in java.xml using default constructors.

Problem

Missing default constructors in org.xml.sax.HandlerBase and org.xml.sax.helpers/DefaultHandler.

Solution

Add explicit default constructors to the two classes.

Specification

--- a/src/java.xml/share/classes/org/xml/sax/HandlerBase.java
+++ b/src/java.xml/share/classes/org/xml/sax/HandlerBase.java
@@ -58,7 +58,10 @@
 public class HandlerBase
     implements EntityResolver, DTDHandler, DocumentHandler, ErrorHandler
 {
-
+    /**
+     * Constructs a {@code HandlerBase}.
+     */
+    public HandlerBase() {}

     ////////////////////////////////////////////////////////////////////
     // Default implementation of the EntityResolver interface.

--- a/src/java.xml/share/classes/org/xml/sax/helpers/DefaultHandler.java
+++ b/src/java.xml/share/classes/org/xml/sax/helpers/DefaultHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -70,7 +70,10 @@
 public class DefaultHandler
     implements EntityResolver, DTDHandler, ContentHandler, ErrorHandler
 {
-
+    /**
+     * Constructs a {@code DefaultHandler}.
+     */
+    public DefaultHandler() {}

     ////////////////////////////////////////////////////////////////////
     // Default implementation of the EntityResolver interface.