RFR [16/java.xml] 8250638: Address reliance on default constructors in java.xml

[Joe Wang]

Hello,

Please review a change to remove reliance of default constructors in 
java.xml.

JBS: https://bugs.openjdk.java.net/browse/JDK-8250638
CSR: https://bugs.openjdk.java.net/browse/JDK-8250800

Patch:

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

////////////////////////////////////////////////////////////////////
      // Default implementation of the EntityResolver interface.
diff --git 
a/src/java.xml/share/classes/org/xml/sax/helpers/DefaultHandler.java 
b/src/java.xml/share/classes/org/xml/sax/helpers/DefaultHandler.java
--- 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.

Thanks,
Joe