ml与java代码相互装换的工具类

ml与java代码相互装换的工具类

这是一个java操作xml文件的工具类，最大的亮点在于能够通过工具类直接生成xml同样层次结构的java代码，也就是说，只要你定义好了xml的模板，就能一键生成java代码。省下了自己再使用工具类写代码的时间，极大得提高了效率。

首先来看看工具类代码

package ateXml;import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;l.XMLConstants;
l.parsers.DocumentBuilder;
l.parsers.DocumentBuilderFactory;
l.parsers.ParserConfigurationException;
l.transform.OutputKeys;
l.transform.Result;
l.transform.Source;
l.transform.Transformer;
l.transform.TransformerException;
l.transform.TransformerFactory;
l.transform.dom.DOMSource;
l.transform.stream.StreamResult;
l.transform.stream.StreamSource;
l.validation.Schema;
l.validation.SchemaFactory;
l.validation.Validator;import org.apachemons.lang3.StringUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
l.sax.SAXException;/*** 操作xml文件以及生成java代码的工具* @author lfq* @since 1.0, Jun 12, 2007*/
public final class XmlUtils {private static final String XMLNS_XSI = "xmlns:xsi";private static final String XSI_SCHEMA_LOCATION = "xsi:schemaLocation";private static final String LOGIC_YES = "yes";private static final String DEFAULT_ENCODE = "UTF-8";private static final String REG_INVALID_CHARS = "&#\d+;";/*** Creates a new document instance.** @return a new document instance* @throws XmlException problem creating a new document*/public static Document newDocument() throws XmlException {Document doc = null;try {doc = wInstance().newDocumentBuilder().newDocument();} catch (ParserConfigurationException e) {throw new XmlException(e);}return doc;}/*** Parses the content of the given XML file as an XML document.** @param file the XML file instance* @return the document instance representing the entire XML document* @throws XmlException problem parsing the XML file*/public static Document getDocument(File file) throws XmlException {InputStream in = getInputStream(file);return getDocument(in);}/*** Parses the content of the given stream as an XML document.** @param in the XML file input stream* @return the document instance representing the entire XML document* @throws XmlException problem parsing the XML input stream*/public static Document getDocument(InputStream in) throws XmlException {Document doc = null;try {DocumentBuilder builder = wInstance().newDocumentBuilder();doc = builder.parse(in);} catch (ParserConfigurationException e) {throw new XmlException(e);} catch (SAXException e) {throw new XmlException(XmlException.XML_PARSE_ERROR, e);} catch (IOException e) {throw new XmlException(XmlException.XML_READ_ERROR, e);} finally {if (in != null) {try {in.close();} catch (IOException e) {// nothing to do}}}return doc;}/*** Creates a root element as well as a new document with specific tag name.** @param tagName the name of the root element* @return a new element instance* @throws XmlException problem generating a new document*/public static Element createRootElement(String tagName) throws XmlException {Document doc = newDocument();Element root = ateElement(tagName);doc.appendChild(root);return root;}/*** Gets the root element from input stream.** @param in the XML file input stream* @return the root element of parsed document* @throws XmlException problem parsing the XML file input stream*/public static Element getRootElementFromStream(InputStream in)throws XmlException {return getDocument(in).getDocumentElement();}/*** Gets the root element from given XML file.** @param fileName the name of the XML file* @return the root element of parsed document* @throws XmlException problem parsing the XML file*/public static Element getRootElementFromFile(File file)throws XmlException {return getDocument(file).getDocumentElement();}/*** Gets the root element from the given XML payload.** @param payload the XML payload representing the XML file.* @return the root element of parsed document* @throws XmlException problem parsing the XML payload*/public static Element getRootElementFromString(String payload)throws XmlException {if (payload == null || im().length() < 1) {throw new XmlException(XmlException.XML_PAYLOAD_EMPTY);}byte[] bytes = null;try {bytes = Bytes(DEFAULT_ENCODE);} catch (UnsupportedEncodingException e) {throw new XmlException(XmlException.XML_ENCODE_ERROR, e);}InputStream in = new ByteArrayInputStream(bytes);return getDocument(in).getDocumentElement();}/*** Gets the descendant elements list from the parent element.** @param parent the parent element in the element tree* @param tagName the specified tag name* @return the NOT NULL descendant elements list*/public static List<Element> getElements(Element parent, String tagName) {NodeList nodes = ElementsByTagName(tagName);List<Element> elements = new ArrayList<Element>();for (int i = 0; i < Length(); i++) {Node node = nodes.item(i);if (node instanceof Element) {elements.add((Element) node);}}return elements;}/*** Gets the immediately descendant element from the parent element.** @param parent the parent element in the element tree* @param tagName the specified tag name.* @return immediately descendant element of parent element, NULL otherwise.*/public static Element getElement(Element parent, String tagName) {List<Element> children = getElements(parent, tagName);if (children.isEmpty()) {return null;} else {(0);}}/*** Gets the immediately child elements list from the parent element.** @param parent the parent element in the element tree* @param tagName the specified tag name* @return the NOT NULL immediately child elements list*/public static List<Element> getChildElements(Element parent, String tagName) {NodeList nodes = ElementsByTagName(tagName);List<Element> elements = new ArrayList<Element>();for (int i = 0; i < Length(); i++) {Node node = nodes.item(i);if (node instanceof Element && ParentNode() == parent) {elements.add((Element) node);}}return elements;}/*** Gets the immediately child element from the parent element.** @param parent the parent element in the element tree* @param tagName the specified tag name* @return immediately child element of parent element, NULL otherwise*/public static Element getChildElement(Element parent, String tagName) {List<Element> children = getChildElements(parent, tagName);if (children.isEmpty()) {return null;} else {(0);}}/*** Gets the value of the child element by tag name under the given parent* element. If there is more than one child element, return the value of the* first one.** @param parent the parent element* @param tagName the tag name of the child element* @return value of the first child element, NULL if tag not exists*/public static String getElementValue(Element parent, String tagName) {String value = null;Element element = getElement(parent, tagName);if (element != null) {value = TextContent();}return value;}/*** Appends the child element to the parent element.** @param parent the parent element* @param tagName the child element name* @return the child element added to the parent element*/public static Element appendElement(Element parent, String tagName) {Element child = OwnerDocument().createElement(tagName);parent.appendChild(child);return child;}/*** Appends the child element as well as value to the parent element.** @param parent the parent element* @param tagName the child element name* @param value the child element value* @return the child element added to the parent element*/public static Element appendElement(Element parent, String tagName,String value) {Element child = appendElement(parent, tagName);child.setTextContent(value);return child;}/*** Appends another element as a child element.** @param parent the parent element* @param child the child element to append*/public static void appendElement(Element parent, Element child) {Node tmp = OwnerDocument().importNode(child, true);parent.appendChild(tmp);}/*** Appends the CDATA element to the parent element.** @param parent the parent element* @param tagName the CDATA element name* @param value the CDATA element value* @return the CDATA element added to the parent element*/public static Element appendCDATAElement(Element parent, String tagName,String value) {Element child = appendElement(parent, tagName);if (value == null) { // avoid "null" word in the XML payloadvalue = "";}Node cdata = OwnerDocument().createCDATASection(value);child.appendChild(cdata);return child;}/*** Converts the Node/Element instance to XML payload.** @param node the node/element instance to convert* @return the XML payload representing the node/element* @throws XmlException problem converting XML to string*/public static String childNodeToString(Node node) throws XmlException {String payload = null;try {Transformer tf = wInstance().newTransformer();Properties props = tf.getOutputProperties();props.setProperty(OutputKeys.OMIT_XML_DECLARATION, LOGIC_YES);tf.setOutputProperties(props);StringWriter writer = new StringWriter();tf.transform(new DOMSource(node), new StreamResult(writer));payload = String();payload = placeAll(REG_INVALID_CHARS, " ");} catch (TransformerException e) {throw new XmlException(XmlException.XML_TRANSFORM_ERROR, e);}return payload;}/*** Converts the Node/Document/Element instance to XML payload.** @param node the node/document/element instance to convert* @return the XML payload representing the node/document/element* @throws XmlException problem converting XML to string*/public static String nodeToString(Node node) throws XmlException {String payload = null;try {Transformer tf = wInstance().newTransformer();Properties props = tf.getOutputProperties();props.setProperty(OutputKeys.INDENT, LOGIC_YES);props.setProperty(OutputKeys.ENCODING, DEFAULT_ENCODE);tf.setOutputProperties(props);StringWriter writer = new StringWriter();tf.transform(new DOMSource(node), new StreamResult(writer));payload = String();payload = placeAll(REG_INVALID_CHARS, " ");} catch (TransformerException e) {throw new XmlException(XmlException.XML_TRANSFORM_ERROR, e);}return payload;}/*** Converts the an XML file to XML payload.** @param file the XML file instance* @return the XML payload representing the XML file* @throws XmlException problem transforming XML to string*/public static String xmlToString(File file) throws XmlException {Element root = getRootElementFromFile(file);return nodeToString(root);}/*** Converts the an XML file input stream to XML payload.** @param in the XML file input stream* @return the payload represents the XML file* @throws XmlException problem transforming XML to string*/public static String xmlToString(InputStream in) throws XmlException {Element root = getRootElementFromStream(in);return nodeToString(root);}/*** Saves the node/document/element as XML file.** @param doc the XML node/document/element to save* @param file the XML file to save* @throws XmlException problem persisting XML file*/public static void saveToXml(Node doc, File file) throws XmlException {OutputStream out = null;try {Transformer tf = wInstance().newTransformer();Properties props = tf.getOutputProperties();props.setProperty(OutputKeys.METHOD, XMLConstants.XML_NS_PREFIX);props.setProperty(OutputKeys.INDENT, LOGIC_YES);tf.setOutputProperties(props);DOMSource dom = new DOMSource(doc);out = getOutputStream(file);Result result = new StreamResult(out);tf.transform(dom, result);} catch (TransformerException e) {throw new XmlException(XmlException.XML_TRANSFORM_ERROR, e);} finally {if (out != null) {try {out.close();} catch (IOException e) {// nothing to do}}}}/*** Validates the element tree context via given XML schema file.** @param doc the XML document to validate* @param schemaFile the XML schema file instance* @throws XmlException error occurs if the schema file not exists*/public static void validateXml(Node doc, File schemaFile)throws XmlException {validateXml(doc, getInputStream(schemaFile));}/*** Validates the element tree context via given XML schema file.** @param doc the XML document to validate* @param schemaStream the XML schema file input stream* @throws XmlException error occurs if validation fail*/public static void validateXml(Node doc, InputStream schemaStream)throws XmlException {try {Source source = new StreamSource(schemaStream);Schema schema = wInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI).newSchema(source);Validator validator = wValidator();validator.validate(new DOMSource(doc));} catch (SAXException e) {throw new XmlException(XmlException.XML_VALIDATE_ERROR, e);} catch (IOException e) {throw new XmlException(XmlException.XML_READ_ERROR, e);} finally {if (schemaStream != null) {try {schemaStream.close();} catch (IOException e) {// nothing to do}}}}/*** Transforms the XML content to XHTML/HTML format string with the XSL.** @param payload the XML payload to convert* @param xsltFile the XML stylesheet file* @return the transformed XHTML/HTML format string* @throws XmlException problem converting XML to HTML*/public static String xmlToHtml(String payload, File xsltFile)throws XmlException {String result = null;try {Source template = new StreamSource(xsltFile);Transformer transformer = wInstance().newTransformer(template);Properties props = OutputProperties();props.setProperty(OutputKeys.OMIT_XML_DECLARATION, LOGIC_YES);transformer.setOutputProperties(props);StreamSource source = new StreamSource(new StringReader(payload));StreamResult sr = new StreamResult(new StringWriter());ansform(source, sr);result = sr.getWriter().toString();} catch (TransformerException e) {throw new XmlException(XmlException.XML_TRANSFORM_ERROR, e);}return result;}/*** Sets the namespace to specific element.** @param element the element to set* @param namespace the namespace to set* @param schemaLocation the XML schema file location URI*/public static void setNamespace(Element element, String namespace,String schemaLocation) {element.setAttributeNS(XMLConstants.XMLNS_ATTRIBUTE_NS_URI,XMLConstants.XMLNS_ATTRIBUTE, namespace);element.setAttributeNS(XMLConstants.XMLNS_ATTRIBUTE_NS_URI, XMLNS_XSI,XMLConstants.W3C_XML_SCHEMA_INSTANCE_NS_URI);element.setAttributeNS(XMLConstants.W3C_XML_SCHEMA_INSTANCE_NS_URI,XSI_SCHEMA_LOCATION, schemaLocation);}/*** Encode the XML payload to legality character.** @param payload the XML payload to encode* @return the encoded XML payload* @throws XmlException problem encoding the XML payload*/public static String encodeXml(String payload) throws XmlException {Element root = createRootElement(XMLConstants.XML_NS_PREFIX);root.setTextContent(payload);return FirstChild());}private static InputStream getInputStream(File file) throws XmlException {InputStream in = null;try {in = new FileInputStream(file);} catch (FileNotFoundException e) {throw new XmlException(XmlException.FILE_NOT_FOUND, e);}return in;}private static OutputStream getOutputStream(File file) throws XmlException {OutputStream in = null;try {in = new FileOutputStream(file);} catch (FileNotFoundException e) {throw new XmlException(XmlException.FILE_NOT_FOUND, e);}return in;}/*** @Desc 把实体类中有的字段直接转为xml节点* @author LV_FQ* @date 2016年12月15日* @param parent* @param formMap* @param fields*/public static void entityToXml(Element parent,  fields){for(String field : fields){String temp = "XmlUtils.appendElement(root, "" + field + "", Str("field"));";System.out.println(temp);XmlUtils.appendElement(parent, field, "取值");}}/*** @Desc 根据xml生成java代码* @author LV_FQ* @date 2016年12月16日* @param file xml文件*/public static void createJavaCode(File file){ateJavaCode(file);}
}class XmlException extends RuntimeException {private static final long serialVersionUID = 381260478228427716L;public static final String XML_PAYLOAD_EMPTY = "pty";public static final String XML_ENCODE_ERROR = &#ding.invalid";public static final String FILE_NOT_FOUND = "found";public static final String XML_PARSE_ERROR = "";public static final String XML_READ_ERROR = &#ad.error";public static final String XML_VALIDATE_ERROR = "";public static final String XML_TRANSFORM_ERROR = &#";public XmlException() {super();}public XmlException(String key, Throwable cause) {super(key, cause);}public XmlException(String key) {super(key);}public XmlException(Throwable cause) {super(cause);}
}/*** @Desc 根据xml的格式生成xml的对应的java生成代码* @author LV_FQ* @date 2016年12月16日 下午2:08:38* @version 1.0**/
class XMLToJavaUtils {public static void createJavaCode(File file) {try {//File file = new File("C:/Users/SUCCESS/l");DocumentBuilderFactory dbFactory = wInstance();DocumentBuilder dBuilder = wDocumentBuilder();Document doc = dBuilder.parse(file);if (doc.hasChildNodes()) {ChildNodes(), null);}} catch (Exception e) {e.printStackTrace();}}private static void printNote(NodeList nodeList, Node parent) {for (int i = 0; i < Length(); i++) {Node node = nodeList.item(i);if (NodeType() == Node.ELEMENT_NODE) {if(parent == null){System.out.println("Element "+ NodeName())+" = ateRootElement(""+ NodeName() +"");");}else{String temp = "XmlUtils.appendElement("+getTagName(parent == null? null : NodeName())+", "" + NodeName();if (node.hasChildNodes() && ChildNodes().getLength() > 1) {System.out.println();//非叶节点把节点的名称加上，以便子节点和父节点做关联temp = "Element " + NodeName()) + " = " + temp + "");";}else{//叶节点把注释加上//temp += "", "value");//" + TextContent();temp += "", ""+ TextContent() +"");";}System.out.println(temp);}if (node.hasChildNodes()) {ChildNodes(), node);}}}}/*** @Desc 把字符串第一个字母转小写* @author LV_FQ* @date 2016年12月16日* @param name* @return*/private static String getTagName(String name){if(StringUtils.isBlank(name)){return "";}String temp = name;temp = temp.substring(0, 1).toLowerCase() + temp.substring(1);return temp;}
}

测试类

package ateXml;import java.io.File;import org.w3c.dom.Element;public class TestXml {public static void main(String[] args) {Element note = ateRootElement("note");XmlUtils.appendElement(note, "to", "George1");XmlUtils.appendElement(note, "from", "John2");XmlUtils.appendElement(note, "heading", "Reminder1");XmlUtils.appendElement(note, "body", "Don't forget the meeting!");XmlUtils.saveToXml(note, new File("/home/lv-success/l"));//使用xml生成工具生成java代码(控制台输出)File file = new File("/home/lv-success/l");ateJavaCode(file);}}

从test中可以看出，工具类通过已有的操作xml文件的方法读取xml的结构，同时根据读取的节点内容直接把对于生成的方法打印到控制台中，如此嵌套打印，最终打印出这个xml文件的相同java层次结构的代码。

如果对生成的java代码有不同要求，大家可以直接修改工具类中的生成java代码的方法。能生成自己最终要求最接近的代码最好，怎么方便怎么来哈。

在这里给大家提供一个学习交流的平台，java架构师群： 558787436

具有1-5工作经验的，面对目前流行的技术不知从何下手，需要突破技术瓶颈的可以加群。

在公司待久了，过得很安逸，但跳槽时面试碰壁。需要在短时间内进修、跳槽拿高薪的可以加群。

如果没有工作经验，但基础非常扎实，对java工作机制，常用设计思想，常用java开发框架掌握熟练的可以加群。