Improve memory (see #389)

org.eclipse.lsp4xml/src/test/java/org/eclipse/lsp4xml/performance/XMLScannerPerformance.java

@@ -0,0 +1,46 @@
+/*******************************************************************************
+* Copyright (c) 2019 Red Hat Inc. and others.
+* All rights reserved. This program and the accompanying materials
+* which accompanies this distribution, and is available at
+* http://www.eclipse.org/legal/epl-v20.html
+*
+* Contributors:
+*     Red Hat Inc. - initial API and implementation
+*******************************************************************************/
+package org.eclipse.lsp4xml.performance;
+
+import java.io.InputStream;
+
+import org.eclipse.lsp4xml.dom.DOMDocumentTest;
+import org.eclipse.lsp4xml.dom.parser.Scanner;
+import org.eclipse.lsp4xml.dom.parser.TokenType;
+import org.eclipse.lsp4xml.dom.parser.XMLScanner;
+
+/**
+ * This utility class is used to check memories with use of XMLScanner with the big file nasa.xml.
+ * 
+ * @author Angelo Zerr
+ *
+ */
+public class XMLScannerPerformance {
+
+	public static void main(String[] args) {
+		InputStream in = DOMDocumentTest.class.getResourceAsStream("/xml/nasa.xml");
+		String text = convertStreamToString(in);
+		// Parse every time the big file with scanner.
+		while (true) {
+			long start = System.currentTimeMillis();
+			Scanner scanner = XMLScanner.createScanner(text);
+			TokenType token = scanner.scan();
+			while (token != TokenType.EOS) {
+				token = scanner.scan();
+			}
+			System.err.println("Parsed 'nasa.xml' with XMLScanner in " + (System.currentTimeMillis() - start) + " ms.");
+		}
+	}
+
+	static String convertStreamToString(InputStream is) {
+		java.util.Scanner s = new java.util.Scanner(is).useDelimiter("\\A");
+		return s.hasNext() ? s.next() : "";
+	}
+}