用java代码编写工具类，实现entity、dao 、service 、serviceImpl自动生成。

参考开源csdn一位博友写的，改动了部分实现自己需求规则

http://blog.csdn.net/u010137431/article/details/46595487

生成配置项：

<?xml version="1.0" encoding="UTF-8"?><root><!-- 模板配置    模板文件路径和model、dao、service对应需要的模板名--><ftl path="\\src\\main\\java\\com\\wjw\\framework\\generate\\ftl"><param name="model">/model.ftl</param><param name="dao">/dao.ftl</param><param name="service">/service.ftl</param></ftl><!-- service.ftl需要的信息   path service包路径   packageName service中的java文件需要指定包名 --><service path="\\src\\main\\java\\com\\wjw\\xincms\\server\\service"><packageName>com.wjw.xincms.server.service</packageName></service><!-- dao.ftl需要的信息  path dao包路径  packageName dao中的java文件需要指定包名 --><dao path="\\src\\main\\java\\com\\wjw\\xincms\\server\\dao"><packageName>com.wjw.xincms.server.dao</packageName></dao><!-- model.ftl需要的信息  path model包路径   packageName model中的java文件需要指定包名    class 实体类名   desc 类名注释 --><models path="\\src\\main\\java\\com\\wjw\\xincms\\entity"><packageName>com.wjw.xincms.entity</packageName><model><className>User</className><desc>用户</desc></model><model><className>Role</className><desc>角色</desc></model></models>
</root>

读取配置项，生成的实体、dao、service的位置，需要生成的实体类等：

package com.wjw.framework.generate;import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
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;
import freemarker.template.TemplateException;public class Generate {public static void main(String[] args) throws IOException, TemplateException, ParserConfigurationException, SAXException {String ftlPath = ""; //模板路径//model参数String ModelftlName = "";  //model模板名称String ModelfilePath = ""; //模板路径String ModelpackgeName = "";//模板包名List<Attr> modellist = new ArrayList<Attr>(); //需要生成的实体对象集合// dao参数String DaoftlName = ""; //dao模板名称String DaofilePath = ""; //dao路径String DaopackgeName = ""; //dao包名//service参数String ServiceftlName = ""; //Service模板名称String ServicefilePath = ""; //service路径String ServicepackgeName = "";//service包名//配置文件位置File  xmlFile = new File(System.getProperty("user.dir"), "\\src\\main\\java\\com\\wjw\\framework\\generate\\GenerateConf.xml");DocumentBuilderFactory  builderFactory =  DocumentBuilderFactory.newInstance();  DocumentBuilder   builder = builderFactory.newDocumentBuilder();  Document  doc = builder.parse(xmlFile);Element rootElement = doc.getDocumentElement(); //获取根元素Node ftlnode = rootElement.getElementsByTagName("ftl").item(0);ftlPath = ((Element)ftlnode).getAttribute("path");NodeList params = ftlnode.getChildNodes();for(int i = 0; i < params.getLength(); i++){//获取对应模板名称Node node = params.item(i);if(node.getNodeType() != Node.ELEMENT_NODE) continue;Element e = (Element)node;if(e.getAttribute("name").trim().equals("model"))  ModelftlName = node.getFirstChild().getNodeValue();if(e.getAttribute("name").trim().equals("dao"))  DaoftlName = node.getFirstChild().getNodeValue();if(e.getAttribute("name").trim().equals("service"))  ServiceftlName = node.getFirstChild().getNodeValue();}//获取对应service参数Node servicenode = rootElement.getElementsByTagName("service").item(0);ServicefilePath = ((Element)servicenode).getAttribute("path");ServicepackgeName = servicenode.getChildNodes().item(1).getFirstChild().getNodeValue();//获取对应dao参数Node daonode = rootElement.getElementsByTagName("dao").item(0);DaofilePath = ((Element)daonode).getAttribute("path");DaopackgeName = daonode.getChildNodes().item(1).getFirstChild().getNodeValue();//获取对应model参数Node modelnode = rootElement.getElementsByTagName("models").item(0);ModelfilePath = ((Element)modelnode).getAttribute("path");params = modelnode.getChildNodes();for(int i = 0; i < params.getLength(); i++){Node node = params.item(i);if(node.getNodeType() != Node.ELEMENT_NODE) continue;Element e = (Element)node;if(e.getNodeName().trim().equals("packageName")) ModelpackgeName = node.getFirstChild().getNodeValue();if(e.getNodeName().trim().equals("model")){Attr attr = new Attr();NodeList attrnode = node.getChildNodes();for(int j = 0; j < attrnode.getLength(); j++){Node anode = attrnode.item(j);if(anode.getNodeType() != Node.ELEMENT_NODE) continue;Element ae = (Element)anode;if(ae.getTagName().trim().equals("className")) attr.setClassName(anode.getFirstChild().getNodeValue());if(ae.getTagName().trim().equals("desc")) attr.setDesc(anode.getFirstChild().getNodeValue());}modellist.add(attr);}}GenerateUtil gt =new GenerateUtil("wjw",ftlPath);gt.GenerateDao(DaoftlName, DaofilePath, DaopackgeName, ModelpackgeName,modellist);gt.GenerateService(ServiceftlName, ServicefilePath, ServicepackgeName, DaopackgeName, ModelpackgeName,modellist);gt.GenerateModel(ModelftlName, ModelfilePath, ModelpackgeName, modellist);}
}

GenerateUtil gt =new GenerateUtil("wjw",ftlPath);//传入生成的作者名 ,生成模板路径

//生成model实体类

gt.GenerateModel(ModelftlName, ModelfilePath, ModelpackgeName, modellist);

//生成dao

gt.GenerateDao(DaoftlName, DaofilePath, DaopackgeName, ModelpackgeName,modellist);

//生成service和serviceImpl实现

gt.GenerateService(ServiceftlName, ServicefilePath, ServicepackgeName, DaopackgeName, ModelpackgeName,modellist);
获取需要生成的参数传入freemarker模板中，写入到指路径下

package com.wjw.framework.generate;import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.StringWriter;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;import org.wjw.utils.DateUtil;
import org.wjw.utils.HumpUtils;import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;/*** @desc 生成工具类* @author wjw* @date 2016年12月21日下午4:31:29*/
public class GenerateUtil {public String author="wjw";//设置默认作者public String ftlPath;//模板所在路径public GenerateUtil() {}public GenerateUtil(String author,String ftlPath) {this.author = author;this.ftlPath = ftlPath;path_Judge_Exist(ftlPath);}/*** @desc  model生成方法* @param ftlName      模板名* @param filePath       model层的路径* @param packageName  model包名* @param list           model参数集合*/public void GenerateModel(String ftlName, String filePath, String packageName, List<Attr> list) throws IOException, TemplateException{path_Judge_Exist(filePath);//实体类需要其他参数Map<String,Object> root = new HashMap<String, Object>();root.put("packageName", packageName);root.put("author", author);for(Attr a : list){String className = a.getClassName();root.put("desc", a.getDesc());root.put("createDate", DateUtil.formatDate(new Date(), "yyyy年MM月dd日aK:mm:ss") );root.put("className", className);root.put("table",  HumpUtils.camelToUnderline2(className));Configuration cfg = new Configuration();String path = System.getProperty("user.dir") + ftlPath;cfg.setDirectoryForTemplateLoading(new File(path));Template template = cfg.getTemplate(ftlName);printFile(root, template, filePath, className);}}/*** @desc  dao生成方法* @param ftlName* @param filePath* @param packageName* @param modelPackageName* @param list* @throws IOException* @throws TemplateException*/public void GenerateDao(String ftlName, String filePath, String packageName, String modelPackageName,List<Attr> list) throws IOException, TemplateException {path_Judge_Exist(filePath);//实体类需要其他参数Map<String,Object> root = new HashMap<String, Object>();root.put("packageName", packageName);root.put("author", author);root.put("modelPackageName", modelPackageName);for(Attr a : list){String modelClassName = a.getClassName();root.put("modelClassName", modelClassName);root.put("desc", a.getDesc());root.put("createDate", DateUtil.formatDate(new Date(), "yyyy年MM月dd日aK:mm:ss") );Configuration cfg = new Configuration();String path = System.getProperty("user.dir") + ftlPath;cfg.setDirectoryForTemplateLoading(new File(path));Template template = cfg.getTemplate(ftlName);printFile(root, template, filePath, modelClassName + "Dao");}}/*** @desc servic接口和实现的生成方法* @param ftlName* @param filePath* @param packageName* @param daoPackageName* @param modelPackageName* @param list* @throws IOException* @throws TemplateException*/public void GenerateService(String ftlName,String filePath, String packageName,String daoPackageName, String modelPackageName,List<Attr> list) throws IOException, TemplateException {String ImplFilePath = filePath + "\\impl";path_Judge_Exist(filePath);path_Judge_Exist(ImplFilePath);Map<String,Object> root = new HashMap<String, Object>();root.put("author", author);root.put("daoPackageName", daoPackageName);root.put("packageName", packageName);root.put("implPackageName", packageName+".impl");root.put("modelPackageName", modelPackageName);for(Attr a : list){String className = a.getClassName();//类名root.put("desc", a.getDesc());root.put("createDate", DateUtil.formatDate(new Date(), "yyyy年MM月dd日aK:mm:ss") );root.put("className", className);root.put("implflag", false);//接口Configuration cfg = new Configuration();String path = System.getProperty("user.dir") + ftlPath;cfg.setDirectoryForTemplateLoading(new File(path));Template template = cfg.getTemplate(ftlName);printFile(root, template, filePath, className + "Service");//生成service接口root.put("implflag", true);//实现printFile(root, template, ImplFilePath, className + "ServiceImpl");//生成service实现}}//判断包路径是否存在public static void path_Judge_Exist(String path){File file = new File(System.getProperty("user.dir"), path);if(!file.exists()) file.mkdirs();}//输出到文件public static void printFile(Map<String, Object> root, Template template, String filePath, String fileName) throws IOException, TemplateException  {String path = System.getProperty("user.dir") + filePath;File file = new File(path, fileName + ".java");if(!file.exists()) file.createNewFile();FileWriter fw = new FileWriter(file);template.process(root, fw);fw.close();}//输出到控制台public static void printConsole(Map<String, Object> root, Template template)throws TemplateException, IOException {StringWriter out = new StringWriter();template.process(root, out);System.out.println(out.toString());}public String getAuthor() {return author;}public void setAuthor(String author) {this.author = author;}public String getFtlPath() {return ftlPath;}public void setFtlPath(String ftlPath) {this.ftlPath = ftlPath;}
}

下面贴出模板model、dao、service模板：

package ${packageName};import javax.persistence.Entity;
import javax.persistence.Table;import com.wjw.framework.spring.persistence.BaseEntity;/*** @desc ${desc}-实体类* @author ${author}* @date ${createDate}*/
@Entity
@Table(name = "${table}")
public class ${className} extends BaseEntity {}

package ${packageName};import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
import org.springframework.data.repository.PagingAndSortingRepository;import ${modelPackageName}.${modelClassName};/*** @desc ${desc}-Dao* @author ${author}* @date ${createDate}*/
public interface ${modelClassName}Dao extends PagingAndSortingRepository<${modelClassName}, String>, JpaSpecificationExecutor<${modelClassName}> {}

<#if !implflag>
package ${packageName};import ${modelPackageName}.${className};/*** @desc ${desc}-服务接口* @author ${author}* @date ${createDate}*/
public interface ${className}Service {public void save(${className} ${className?lower_case});}
<#else>
package ${implPackageName};import ${modelPackageName}.${className};
import ${daoPackageName}.${className}Dao;
import ${packageName}.${className}Service;import org.springframework.beans.factory.annotation.Autowired;/*** @desc ${desc}-服务实现* @author ${author}* @date ${createDate}*/
public class  ${className}ServiceImpl implements  ${className}Service {@Autowiredprivate ${className}Dao ${className?lower_case}Dao;@Overridepublic void save(${className} ${className?lower_case}) {// TODO Auto-generated method stub}}
</#if>

下面是接收需要生成的实体对象类：

package com.wjw.framework.generate;public class Attr {private String className;  //类名private String desc; //描述public Attr() {// TODO Auto-generated constructor stub}public Attr(String className,String desc) {this.className=className;this.desc=desc;}public String getClassName() {return className;}public void setClassName(String className) {this.className = className;}public String getDesc() {return desc;}public void setDesc(String desc) {this.desc = desc;}}

最后生成的代码截图

可根据自己用的框架来修改模板实现自己的需求。

我去掉了具体的字段生成，在需求中字段是经常增加修改的，添加几个字段用eclipse的快捷键shirt+alt+s也能快速生成set、get方法，通过数据库生成实体类我用不到，我的是实体类通过hibernate生成数据库表，根据自己的需求修改生成规则