在Java中读取和更新XML文件中的多级元素

Question

I have below xml file I want to change some of attribute that xml file using java code. We have changed some attribute here through java code

Below Xml file contains related information.

    <Order>
    <AllowedModifications>
    <Modification ModificationType="CHANGE_CUSTOM_ATTRIBUTES" ThroughOverride="Y"/>
    <Modification ModificationType="RECEIVING_NODE" ThroughOverride="Y"/>
    <Modification ModificationType="OTHERS" ThroughOverride="Y"/>
    </AllowedModifications>
    </Order>

Like if ModificationType=OTHERS then we have to change ThroughOverride value =Y. How we can do it with the help of java code.

I tried below code but it is not changing.

    Element eleAllowedModifications = Util.getChildElement(eleOrderRoot,"AllowedModifications")
    System.out.println("First  Element "+eleAllowedModifications.getNodeName()); 
    Node staff = xmlFile.getElementsByTagName("Modification").item(0);
    NamedNodeMap attr = staff.getAttributes();
       for (int i = 0; i < attr.getLength(); i++) {
    Node nodeAttr = attr.getNamedItem("ModificationType");
    MoficationTYp =String.valueOf(nodeAttr);
    Node nodeAttr1= attr.getNamedItem("ThroughOverride");   
    MoficationTp =String.valueOf(nodeAttr);
    }

    if (MoficationTYp=="OTHERS") {
    for (int i = 0; i < attr.getLength(); i++) {
    Node nodeAttr = attr.getNamedItem("ThroughOverride");
    MoficationTYp =String.valueOf(nodeAttr);
    nodeAttr.setNodeValue("Y");                 
    }

    }

Here it is not changing that value of ThroughOverride attribute .

Answer 1

If you use an XML library (Disclosure: I'm affiliated with that project), you can get your result with much less code:

public class UpdateOrder {

    public interface Order {
        @XBUpdate("//Modification[@ModificationType='OTHERS']/@ThroughOverride")
        void updateOrder(String value);
    }
    public static void main(String[] args) throws IOException {    
        Order order = new XBProjector(Flags.TO_STRING_RENDERS_XML).io().url("res://data.xml").read(Order.class);
        order.updateOrder("N");
        System.out.println(order.toString());
    }

}

This program prints out:

<Order>
    <AllowedModifications>
        <Modification ModificationType="CHANGE_CUSTOM_ATTRIBUTES" ThroughOverride="Y"/>
        <Modification ModificationType="RECEIVING_NODE" ThroughOverride="Y"/>
        <Modification ModificationType="OTHERS" ThroughOverride="N"/>
    </AllowedModifications>
</Order>

Answer 2

Well, I'd rater use the following code (for example):

    Element eleAllowedModifications = Util.getChildElement(eleOrderRoot,"AllowedModifications");
    System.out.println("First  Element "+ eleAllowedModifications.getNodeName());
    Element staff = (Element)xmlFile.getElementsByTagName("Modification").item(0);
    moficationTyp = staff.getAttribute("ModificationType");
    //moficationTp = String.valueOf(nodeAttr);
    if (moficationTyp.equals("OTHERS")) {
       staff.setAttribute("ThroughOverride", "Y");
    }

Other comments:

• variable names (eg MoficationTYp ) should start with a lowercase letter.
• the loops are not useful here
• String.valueOf() does not seems appropriate to me here.