DOM4J对XML文档的读写增删改等

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.Iterator;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
public class MyTest {
  Document doc = null;
  public MyTest() throws DocumentException, IOException, SAXException {
    Document doc = loadXML("class.xml"); // 载入XML文档
    System.out.println(doc.asXML());
    printDoc(doc); // 打印XML文档
    storeDoc(doc, "new.xml"); // 把XML文档存入硬盘
    doc = valideDoc("class.xml"); // 校验dtd XML文档
    printDoc(doc);
    doc = validateDocBySxd("classSchema.xml"); // 校验Schema文档
    printDoc(doc);
    String url = getClass().getResource("/xml/dom4j/wkjava/class.xsd").toString();
    doc = validateDocBySxd("classSchema.xml", url); // 校验Schema文档（俩参数）
    printDoc(doc);
    doc = createDoc(); // 创建Schema文档
    storeDoc(doc, "root.xml");
    doc = validateDocBySxd("classSchema.xml");
    updateZip(doc, "102202"); // 在文档中修改原属
    printDoc(doc);
    doc = validateDocBySxd("classSchema.xml");
    printNames(doc); // 打印文档中所有学生名字
    System.out.println(getStudentCount(doc));
  }
  public static void main(String[] args) {
    try {
      ne