Undo JDK6 hack

[csware]

Undo AutoClosable hack introduced for JDK6 compatibility.

This is safe to do, as it was added in JDK7 and the Java-HTML-Sanitizer now requires JDK9 (even requiring 8 would still be ok)

This basically reverts commit f7e0924 (and commit 74c6dd0).

[mikesamuel]

Do we have any other tests that closing an autocloseable closes the underlying appendable?

[csware]

The original code (to which I reverted), also had no tests.

[csware]

How is this supposed to be used?

package org.owasp.html;

import java.io.Closeable;
import java.io.IOException;

import junit.framework.TestCase;

@SuppressWarnings("javadoc")
public class AutoCloseableHtmlStreamRendererTest extends TestCase {
	  public static void testBlup() throws Exception {
	    PolicyFactory policyBuilder = new HtmlPolicyBuilder()
	      .allowAttributes("href").onElements("a")
	      .allowStandardUrlProtocols()
	      .allowElements("a")
	      .toFactory();

	    AutoClosableAppender autoClosableAppender = new AutoClosableAppender();
	    assertFalse(autoClosableAppender.closed);
		try (AutoCloseable renderer = (AutoCloseable)HtmlStreamRenderer.create(autoClosableAppender,
				Handler.DO_NOTHING,
				Handler.DO_NOTHING)) {
		// Use the policy defined above to sanitize the HTML.
		HtmlSanitizer.sanitize("<a href=http://example.com>A link</a>", policyBuilder.apply((HtmlStreamRenderer)renderer));
		}
		assertTrue(autoClosableAppender.closed);
	  }

	private static class AutoClosableAppender implements Appendable, AutoCloseable {
		public boolean closed = false;
		@Override
		public void close() throws Exception {
			closed = true;
		}

		@Override
		public Appendable append(CharSequence csq) throws IOException {
			return this;
		}

		@Override
		public Appendable append(CharSequence csq, int start, int end) throws IOException {
			return this;
		}

		@Override
		public Appendable append(char c) throws IOException {
			return this;
		}
	}
}

try (AutoCloseableHtmlStreamRenderer renderer = (AutoCloseableHtmlStreamRenderer)HtmlStreamRenderer.create(autoClosableAppender, ..)) { cannot be used by users, as AutoCloseableHtmlStreamRenderer is package scoped.

[mikesamuel]

Yeah. Java has intersection types but doesn't allow mentioning them.

[csware]

If this is the intended usage, maybe we need another factory method and make the inner-classes public