Merge pull request #16079 from anujgaud/ag/invalid-characters-xml

BAEL-6534 Add InvalidCharactersUnitTest.java

xml-2/src/test/java/com/baeldung/xml/invalidcharacters/InvalidCharactersUnitTest.java

@@ -0,0 +1,69 @@
+package com.baeldung.xml.invalidcharacters;
+
+import org.w3c.dom.Document;
+import org.xml.sax.InputSource;
+import org.xml.sax.SAXParseException;
+
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import java.io.StringReader;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class InvalidCharactersUnitTest {
+
+    @Test
+    void givenXml_whenReservedCharacters_thenThrowException() {
+        String invalidXmlString = "<?xml version=\"1.1\" encoding=\"UTF-8\"?><root><name>John & Doe</name></root>";
+        assertThrowsExactly(SAXParseException.class, () -> parseXmlString(invalidXmlString));
+    }
+
+    @Test
+    void givenXml_whenReservedCharactersEscaped_thenSuccess() {
+        String validXmlString = "<?xml version=\"1.1\" encoding=\"UTF-8\"?><root><name>John &amp; Doe</name></root>";
+
+        assertDoesNotThrow(() -> {
+            Document document = parseXmlString(validXmlString);
+
+            assertNotNull(document);
+            assertEquals("John & Doe", document.getElementsByTagName("name").item(0).getTextContent());
+        });
+    }
+    
+    @Test
+    void givenXml_whenUsingCdataForReservedCharacters_thenSuccess() {
+        String validXmlString = "<?xml version=\"1.1\" encoding=\"UTF-8\"?><root><name><![CDATA[John & Doe]]></name></root>";
+
+        assertDoesNotThrow(() -> {
+            Document document = parseXmlString(validXmlString);
+
+            assertNotNull(document);
+            assertEquals("John & Doe", document.getElementsByTagName("name").item(0).getTextContent());
+        });
+    }    
+
+    @Test
+    void givenXml_whenUnicodeCharacters_thenThrowException() {
+        String invalidXmlString = "<?xml version=\"1.1\" encoding=\"UTF-8\"?><root><name>John \u001E Doe</name></root>";
+        assertThrowsExactly(SAXParseException.class, () -> parseXmlString(invalidXmlString));
+    }
+
+    @Test
+    void givenXml_whenUnicodeCharactersEscaped_thenSuccess() {
+        String validXmlString = "<?xml version=\"1.1\" encoding=\"UTF-8\"?><root><name>John &#x1E; Doe</name></root>";
+        assertDoesNotThrow(() -> {
+            Document document = parseXmlString(validXmlString);
+
+            assertNotNull(document);
+            assertEquals("John \u001E Doe", document.getElementsByTagName("name").item(0).getTextContent());
+        });
+    }
+
+    private Document parseXmlString(String xmlString) throws Exception {
+        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+        DocumentBuilder builder = factory.newDocumentBuilder();
+        InputSource inputSource = new InputSource(new StringReader(xmlString));
+        return builder.parse(inputSource);
+    }
+}