DOMParserUtil { public static void setAttributeValue(Document document, String containerNodeName, String attributeName, String attributeValue) { asStream(document.getElementsByTagName(containerNodeName)) .map(Node::getAttributes) .map(attributes -> attributes.getNamedItem(attributeName)) .filter(Objects::nonNull) .forEach(attributeNode -> attributeNode.setNodeValue(attributeValue)); } private  DOMParserUtil(); static String cleanupNodes(String fullXml, String containerNodeName, String nodeToRemoveName); static void cleanupNodes(Document document, String containerNodeName, String nodeToRemoveName); static void replaceNodeText(Document document, String containerNodeName, String nodeName, String toReplace, String replacement); static String replaceNodeName(Document document, String containerNodeName, String childNodeNameToReplace, String childNodeNameReplacement); static String getAttributeValue(Node containerNode, String attributeName); static Map<Node, String> getAttributeValues(Document document, String containerNodeName, String attributeName); static Map<Node, String> getAttributeValues(Document document, String attributeName); static void setAttributeValue(Document document, String containerNodeName, String attributeName, String attributeValue); static Map<Node, Node> createNodes(Document document, String containerNodeName, String childNodeName, String nodeContent); static Map<Node, Node> createNestedNodes(Document document, String mainContainerNodeName, String containerNodeName, String childNodeName, String nodeContent); static Node createNodeAtPosition(Node containerNode, String nodeToCreateName, String nodeContent, Integer position); static Map<Node, List<Node>> getChildrenNodesMap(String fullXml, String containerNodeName, String childNodeName); static Map<Node, List<Node>> getChildrenNodesMap(Document document, String containerNodeName, String childNodeName); static Map<Node, List<Node>> getChildrenNodesMap(Node node, String containerNodeName, String childNodeName); static List<Node> getChildrenNodesList(Node node, String childNodeName); static Map<Node, List<Node>> getNestedChildrenNodesMap(Document document, String mainContainerNodeName, String containerNodeName, String childNodeName); static List<Node> getNestedChildrenNodesList(Document document, String grandParentNodeName, String parentNodeName, String childNodeName); static List<Node> getNestedChildrenNodesList(Node node, String containerName, String childNodeName); static Document getDocument(String xml); static String getString(Document toRead);  }
@Test public void setAttributeValue() throws Exception { final String newValue = "NEW_VALUE"; Document document = DOMParserUtil.getDocument(XML); DOMParserUtil.setAttributeValue(document, MAIN_NODE, MAIN_ATTRIBUTE_NAME, newValue); Map<Node, String> retrieved = DOMParserUtil.getAttributeValues(document, MAIN_NODE, MAIN_ATTRIBUTE_NAME); assertEquals(retrieved.values().toArray()[0], newValue); DOMParserUtil.setAttributeValue(document, MAIN_NODE, NOT_EXISTING, newValue); retrieved = DOMParserUtil.getAttributeValues(document, MAIN_NODE, NOT_EXISTING); assertTrue(retrieved.isEmpty()); DOMParserUtil.setAttributeValue(document, CHILD_NODE, CHILD_ATTRIBUTE_NAME, newValue); retrieved = DOMParserUtil.getAttributeValues(document, CHILD_NODE, CHILD_ATTRIBUTE_NAME); assertEquals(2, retrieved.size()); retrieved.values().forEach(attributeValue -> assertEquals(newValue, attributeValue)); }