Question

我试图从同一个类中不同方法的方法中读取返回的ArrayList。我的阅读方法看起来像

public static ArrayList<String> readXml(String[] args) throws Exception {
//        String baseServer;
//        String FirstName;

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();

        //Parsing of Book.xml is done here
        Document document = builder.parse(new File("C://Javaseleniumworld/Book.xml"));
        document.getDocumentElement().normalize();

        ArrayList<String> testData = new ArrayList<>();

//        double[] dataList = new double[100];
        NodeList node = document.getElementsByTagName("TestData");
//        NodeList nodeList = document.getDocumentElement().getChildNodes();
        System.out.println("TestData Details");
        System.out.println("________________________________________________");


        for (int i = 0; i < node.getLength(); i++) {
            //We have encountered an <employee> tag.
            Node currentNode = node.item(i);
            if (currentNode.getNodeType() == Node.ELEMENT_NODE) {
                Element element = (Element) currentNode;
                NodeList blocksserverElementList = element.getElementsByTagName("server");

//                   NodeList blocksServerElementList = element.getElementsByTagName("server");
                Element blocksServer = (Element) blocksserverElementList.item(0);
//               NodeList blocksServer1 = blocksServer.getChildNodes();
                String baseServer = ((Node) blocksServer).getNodeValue();
                System.out.println("Mail Servername:" + blocksServer);
                testData.add(baseServer);

                NodeList firstNameElementList = element.getElementsByTagName("firstname");
                Element UName = (Element) firstNameElementList.item(0);
//                NodeList UName = UName.getChildNodes();
                String FirstName1 = ((Node) UName).getNodeValue();
                System.out.println("First Name:" + FirstName1);
                testData.add(FirstName1);
//                return testData;
            }
        }

       return testData;
    }

现在我想用另一种方法

读取返回的testData

ArrayList returnedData = StartCaseJava.readXml（new String [1]）;

我尝试打印returnedData来检查内容，但没有显示任何内容。

Answer 1

public void printStringList(List<String> list){
    for(String item : list){
        System.out.println(item);
    }
}

Answer 2

You can iterate over the list in java as below:

    ArrayList<String> sampleList = new ArrayList<String>();
    sampleList.add("Element A");
    sampleList.add("Element B");
    sampleList.add("Element C");

    // traditional way
    System.out.println("Traditional : ");
    for (int i = 0; i < sampleList.size(); i++) {
        System.out.println(sampleList.get(i));
    }
    // for each
    System.out.println("For each : ");
    for (String element : sampleList) {
        System.out.println(element);
    }
    // functional java 8 way
    System.out.println("Functional looping : ");
    sampleList.stream().forEach((element) -> {
        System.out.println(element);
    });

读取方法中返回的ArrayList - java

2 个答案: