xml與java代碼相互裝換的工具類
首先來看看工具類代碼
package com.lfq.createXml;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
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;
import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import org.apache.commons.lang3.StringUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
/**
- 操作xml文件以及生成java代碼的工具
- @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 = DocumentBuilderFactory.newInstance().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 = DocumentBuilderFactory.newInstance()
.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 = doc.createElement(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 || payload.trim().length() < 1) {
throw new XmlException(XmlException.XML_PAYLOAD_EMPTY);
}byte[] bytes = null;
try {
bytes = payload.getBytes(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 = parent.getElementsByTagName(tagName);
List<Element> elements = new ArrayList<Element>();for (int i = 0; i < nodes.getLength(); 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 {
return children.get(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 = parent.getElementsByTagName(tagName);
List<Element> elements = new ArrayList<Element>();for (int i = 0; i < nodes.getLength(); i++) {
Node node = nodes.item(i);
if (node instanceof Element && node.getParentNode() == 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 {
return children.get(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 = element.getTextContent();
}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 = parent.getOwnerDocument().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 = parent.getOwnerDocument().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 payload
value = "";
}Node cdata = child.getOwnerDocument().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 = TransformerFactory.newInstance().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 = writer.toString(); payload = payload.replaceAll(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 = TransformerFactory.newInstance().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 = writer.toString(); payload = payload.replaceAll(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 = TransformerFactory.newInstance().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 = SchemaFactory.newInstance(
XMLConstants.W3C_XML_SCHEMA_NS_URI).newSchema(source);Validator validator = schema.newValidator(); 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 = TransformerFactory.newInstance()
.newTransformer(template);Properties props = transformer.getOutputProperties(); props.setProperty(OutputKeys.OMIT_XML_DECLARATION, LOGIC_YES); transformer.setOutputProperties(props); StreamSource source = new StreamSource(new StringReader(payload)); StreamResult sr = new StreamResult(new StringWriter()); transformer.transform(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 childNodeToString(root.getFirstChild());
}
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 把實體類中有的字段直接轉為xml節點
- @author LV_FQ
- @date 2016年12月15日
- @param parent
- @param formMap
-
@param fields
*/
public static void entityToXml(Element parent, String... fields){
for(String field : fields){
String temp = "XmlUtils.appendElement(root, \"" + field + "\", decHeadFormMap.getStr(\"field\"));";
System.out.println(temp);XmlUtils.appendElement(parent, field, "取值");
}
}
/**
- @Desc 根據xml生成java代碼
- @author LV_FQ
- @date 2016年12月16日
- @param file xml文件
*/
public static void createJavaCode(File file){
XMLToJavaUtils.createJavaCode(file);
}
}
class XmlException extends RuntimeException {
private static final long serialVersionUID = 381260478228427716L;
public static final String XML_PAYLOAD_EMPTY = "xml.payload.empty";
public static final String XML_ENCODE_ERROR = "xml.encoding.invalid";
public static final String FILE_NOT_FOUND = "xml.file.not.found";
public static final String XML_PARSE_ERROR = "xml.parse.error";
public static final String XML_READ_ERROR = "xml.read.error";
public static final String XML_VALIDATE_ERROR = "xml.validate.error";
public static final String XML_TRANSFORM_ERROR = "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 根據xml的格式生成xml的對應的java生成代碼
- @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/Desktop/temp.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(file);
if (doc.hasChildNodes()) {
printNote(doc.getChildNodes(), null);
}
} catch (Exception e) {
e.printStackTrace();
}
}private static void printNote(NodeList nodeList, Node parent) {
for (int i = 0; i < nodeList.getLength(); i++) {
Node node = nodeList.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {if(parent == null){ System.out.println("Element "+ getTagName(node.getNodeName())+" = XmlUtils.createRootElement(\""+ node.getNodeName() +"\");"); }else{ String temp = "XmlUtils.appendElement("+getTagName(parent == null? null : parent.getNodeName())+", \"" + node.getNodeName(); if (node.hasChildNodes() && node.getChildNodes().getLength() > 1) { System.out.println(); //非葉節點把節點的名稱加上,以便子節點和父節點做關聯 temp = "Element " + getTagName(node.getNodeName()) + " = " + temp + "\");"; }else{ //葉節點把註釋加上 //temp += "\", \"value\");//" + node.getTextContent(); temp += "\", \""+ node.getTextContent() +"\");"; } System.out.println(temp); } if (node.hasChildNodes()) { printNote(node.getChildNodes(), node); } } }
}
/**
- @Desc 把字符串第一個字母轉小寫
- @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;
}
}
測試類
package com.lfq.createXml;
import java.io.File;
import org.w3c.dom.Element;
public class TestXml {
public static void main(String[] args) {
Element note = XmlUtils.createRootElement("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/Desktop/temp.xml"));
//使用xml生成工具生成java代碼(控制臺輸出)
File file = new File("/home/lv-success/Desktop/temp.xml");
XmlUtils.createJavaCode(file);
}
}
從test中可以看出,工具類通過已有的操作xml文件的方法讀取xml的結構,同時根據讀取的節點內容直接把對於生成的方法打印到控制臺中,如此嵌套打印,最終打印出這個xml文件的相同java層次結構的代碼。
如果對生成的java代碼有不同要求,大家可以直接修改工具類中的生成java代碼的方法。能生成自己最終要求最接近的代碼最好,怎麽方便怎麽來哈。
xml與java代碼相互裝換的工具類