XML 的 RUD

    在工作中使用 XML 已经很长时间了,不过长久以来都是进行的读操作,或者在生成 XML 时完全使用 StringBuffer 来构造。进行完整的读取、添加、删除、修改还是最近的事情。在这里我采用的是 DOM4J,其实呢这些内容都很简单,如果愿意,各位大可直接参考官方的 Cookbook(http://www.dom4j.org/cookbook.html)和 Quick Start(http://www.dom4j.org/guide.html)。
   
对于给定的 XML 文件,其结构如下:

 

 
  10290
 

 
  10286
 

 
  10287
 

 

    
为以上 XML 文件构造 Propertys 类:

 public class Propertys {
 
 private String name;
 private String description;
 private String field;

 public String getDescription() {
  return description;
 }

 public void setDescription(String description) {
  this.description = description;
 }

 public String getField() {
  return field;
 }

 public void setField(String field) {
  this.field = field;
 }

 public String getName() {
  return name;
 }

 public void setName(String name) {
  this.name = name;
 }
}

读取方法(返回包含 Propertys 的列表):
   

  public List getAll() {
  List list = new ArrayList();
  try {
   InputStream is = getClass().getResourceAsStream("/navigation.xml");
   SAXReader reader = new SAXReader();      
   Document document = reader.read(is);
   Element root = document.getRootElement();
   Iterator lv = root.elementIterator("propertset");
   Element el = null;
   while (lv.hasNext()) {
    Propertys property=new Propertys();
    el = (Element) lv.next();
    property.setName(el.attributeValue("name"));
    property.setDescription(el.attributeValue("description"));
    property.setField(el.elementText("field"));
    list.add(property);
   }
  } catch (Exception e) {
   e.printStackTrace();
  }
  return list;
 }

添加新节点(成功返回 1 否则 0):
       

  public int saveProperty(Propertys property) {
  try {
   InputStream is = getClass().getResourceAsStream("/navigation.xml");
   SAXReader reader = new SAXReader();      
   Document document = reader.read(is);
   Element root = document.getRootElement();
   root.addElement("propertset")
    .addAttribute("name",property.getName())
    .addAttribute("description",property.getDescription())
    .addElement("field").addText(property.getField());
   
   OutputFormat outformat = OutputFormat.createPrettyPrint();
   outformat.setEncoding("GBK");
   FileWriter out = new FileWriter(
     System.getProperty("user.dir")
     +"/web/WEB-INF/classes/navigation.xml");
   XMLWriter writer=new XMLWriter(out,outformat);
   writer.write(document);
   writer.close();
   return 1;
  } catch (Exception e) {
   e.printStackTrace();
  }
  return 0;
 }

更新节点(按照 name 属性查找):
   

  public int updateProperty(String pro,Propertys property) {
  try {
   InputStream is = getClass().getResourceAsStream("/navigation.xml");
   SAXReader reader = new SAXReader();      
   Document document = reader.read(is);
   Element root = document.getRootElement();
   Iterator lv = root.elementIterator("propertset");
   Element el = null;
   while (lv.hasNext()) {
    el = (Element) lv.next();
    if (el.attributeValue("name").equals(pro)) {
     el.setAttributeValue("name",property.getName());
     el.setAttributeValue("description",property.getDescription());
     el.element("field").setText(property.getField());
    }
   }

   OutputFormat outformat = OutputFormat.createPrettyPrint();
   outformat.setEncoding("GBK");
   FileWriter out = new FileWriter(
     System.getProperty("user.dir")
     +"/web/WEB-INF/classes/navigation.xml");
   XMLWriter writer=new XMLWriter(out,outformat);
   writer.write(document);
   writer.close();
   return 1;
  } catch (Exception e) {
   e.printStackTrace();
  }
  return 0;
 }

删除节点:
   

  public int delProperty(String pro) {
  try {
   InputStream is = getClass().getResourceAsStream("/navigation.xml");
   SAXReader reader = new SAXReader();      
   Document document = reader.read(is);
   Element root = document.getRootElement();
   Iterator lv = root.elementIterator("propertset");
   Element el = null;
   while (lv.hasNext()) {
    el = (Element) lv.next();
    if (el.attributeValue("name").equals(pro)) {
     el.detach();
    }
   }

   OutputFormat outformat = OutputFormat.createPrettyPrint();
   outformat.setEncoding("GBK");
   FileWriter out = new FileWriter(
     System.getProperty("user.dir")
     +"/web/WEB-INF/classes/navigation.xml");
   XMLWriter writer=new XMLWriter(out,outformat);
   writer.write(document);
   writer.close();
   return 1;
  } catch (Exception e) {
   e.printStackTrace();
  }
  return 0;
 }


   

(请注意!引用、转贴本文应注明原作者:Rosen Jiang  以及出处:http://blog.csdn.net/rosen

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