美文网首页
ssm学习笔记精选(1)

ssm学习笔记精选(1)

作者: 子枫Eric | 来源:发表于2020-06-29 22:43 被阅读0次

    1.判断提交方式
    if(request.getMethod().equals("POST")){}

    2.返回json
    @ResponseBody
    3.限定请求方式
    @RequestMapping(value="/login",method= RequestMethod.POST)
    4.session

    //   String a = "aaaaaa";
    //    //当前用户的会话对象”为空(第一次访问时)则创建一个新的会话对象返回
    //            HttpSession session = request.getSession(true);
    //            System.out.println("session_a:"+session.getAttribute("session_a"));
    //    //        创建session
    //            session.setAttribute("session_a",a);
    //            String b = "bbbbbbb";
    //            session.setAttribute("session_b" , b);
    //    //        获取session
    //            System.out.println("session_a"+session.getAttribute("session_a"));
    //            System.out.println("session_b"+session.getAttribute("session_b"));
    

    5.controller传参到视图

    第一种
        @Autowired
            private AccountService accountService;
        @RequestMapping("/index")
        public String index(Model model) {
                //调动业务层方法service
               List<Account> list =  accountService.findAll();
                //存进数据
                model.addAttribute("list",list);
                    return "admin/login/index";
        }
        
    第二种
            ModelAndView mv=new ModelAndView();
            mv.addObject("userinfos",all);
            mv.setViewName("allUser");
            return mv
    
    1. 实现MySQL自动生成实体类
      MySQLGeneratorEntityUtil.java
    package com.zf.utiles;
    
    import java.io.File;
    import java.io.FileWriter;
    import java.io.IOException;
    import java.io.PrintWriter;
    import java.sql.Connection;
    import java.sql.DatabaseMetaData;
    import java.sql.DriverManager;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.sql.ResultSetMetaData;
    import java.sql.Statement;
    import java.text.SimpleDateFormat;
    import java.util.ArrayList;
    import java.util.Date;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    
    
    public class MySQLGeneratorEntityUtil {
         //表名
        private String tableName;
         //列名数组
        private String[] colNames;
         //列名类型数组
        private String[] colTypes;
        //列名大小数组
        private int[] colSizes;
        //列名注释
        private Map colNamesComment = new HashMap();
         //是否需要导入包java.util.*
        private boolean needUtil = false;
         //是否需要导入包java.sql.*
        private boolean needSql = false;
        //是否需要导入包java.math.BigDecimal
        private boolean needBigDecimal = false;
         //是否创建EntityHelper
        private boolean needEntityHelper = true;
        private static final SimpleDateFormat SDF = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        private static final String SQL = "SELECT * FROM ";// 数据库操作
    
        // 数据库配置信息
        private static final String URL = "jdbc:mysql://127.0.0.1:3306/zfadmin_java";
        private static final String NAME = "root";
        private static final String PASS = "";
        private static final String DRIVER = "com.mysql.jdbc.Driver";
    
        //指定实体生成所在包的路径
        private static String basePath = new File("").getAbsolutePath();
        //指定包名
        private static String packageOutPath = "com.zf.entity";
        //作者名字
        private String authorName = "子枫";
        //指定需要生成的表的表名,全部生成设置为null
        private String[] generateTables = null;
         //主键
        private static String pk;
    
        private MySQLGeneratorEntityUtil() {
        }
    
        /**
         * @description 生成class的所有内容
         */
        private String parse() {
            StringBuffer sb = new StringBuffer();
            sb.append("package " + packageOutPath + ";\r\n");
            sb.append("\r\n");
            // 判断是否导入工具包
            if (needUtil) {
                sb.append("import java.util.Date;\r\n");
             }
            if (needSql) {
                sb.append("import java.sql.*;\r\n");
             }
    
           for (int i = 0; i < colNames.length; i++) {
               String hasbd = sqlType2JavaType(colTypes[i]);
               if(hasbd =="BigDecimal" || "BigDecimal".equals(hasbd)) {needBigDecimal=true;}
            }
           if(needBigDecimal) {
               sb.append("import java.math.BigDecimal;\r\n");
            }
             // 注释部分
            sb.append("/**\r\n");
            sb.append(" * table name:  " + tableName + "\r\n");
            sb.append(" * author name: " + authorName + "\r\n");
            sb.append(" * create time: " + SDF.format(new Date()) + "\r\n");
            sb.append(" */ \r\n");
            // 实体部分
            String classExtends = "";
            if(needEntityHelper) {
                classExtends=" extends EntityHelper";
              }
            sb.append("public class " + under2camel(tableName, true) + classExtends + "{\r\n\r\n");
    
            processAllAttrs(sb);// 属性
            sb.append("\r\n");
            processConstructor(sb);//构造函数
            processAllMethod(sb);// get set方法
            processToString(sb);
            if(needEntityHelper) {
                 processEntityHelper(sb,pk);
              }
            sb.append("}\r\n");
            return sb.toString();
        }
    
        /**
         * @param sb
         * @description 生成所有成员变量及注释
         * @author paul
         * @version V1.0
         */
        private void processAllAttrs(StringBuffer sb) {
            for (int i = 0; i < colNames.length; i++) {
                if(colNamesComment.get(colNames[i])!=null &&!"".equals(colNamesComment.get(colNames[i]))) {
                    sb.append("\t/*"+colNamesComment.get(colNames[i])+"*/\r\n");
                }
              sb.append("\tprivate " + sqlType2JavaType(colTypes[i]) + " " + colNames[i] + ";\r\n");
            }
        }
        /**
         * EntityHelper
         * @param sb
         * @param pk
         */
       private void processEntityHelper(StringBuffer sb,String pk) {
           sb.append("\t@Override\r\n");
           sb.append("\tpublic String getPrimaryKey() {\r\n");
           sb.append("\t\treturn \""+pk+"\";\r\n");
           sb.append("\t}\r\n");
       }
        /**
         * 重写toString()方法
         * @param sb
         */
        private void processToString(StringBuffer sb) {
            sb.append("\t@Override\r\n\tpublic String toString() {\r\n");
            sb.append("\t\treturn \"" +tableName + "[\" + \r\n");
            for (int i = 0; i < colNames.length; i++) {
                if (i != 0)
                    sb.append("\t\t\t\", ");
                if (i == 0)
                    sb.append("\t\t\t\"");
                sb.append(colNames[i] + "=\" + "
                        + colNames[i]).append(" + \r\n");
                if (i == colNames.length - 1) {
                    sb.append("\t\t\t\"]\";\r\n");
                }
            }
            sb.append("\t}\r\n");
        }
        /**
         * 构造函数
         * @param sb
         */
        private void processConstructor(StringBuffer sb) {
             StringBuffer p = new StringBuffer();
             StringBuffer v = new StringBuffer();
             for(int i = 0; i < colNames.length; i++) {
                 p.append(sqlType2JavaType(colTypes[i])+" "+colNames[i]);
                 if(i!=colNames.length-1) {
                     p.append(",");
                 }
                 v.append("\t\tthis."+colNames[i]+"="+colNames[i]+";\r\n");
             }
             //无参数构造函数
            sb.append("\tpublic "+under2camel(tableName,true)+"() {\r\n");
            sb.append("\t\tsuper();\r\n");
            sb.append("\t}\r\n");
             //带参构造函数
            sb.append("\tpublic "+under2camel(tableName,true)+"("+p.toString()+") {\r\n");
            sb.append(v.toString());
            sb.append("\t}\r\n");
        }
    
        /**
         * @param sb
         * @description 生成所有get/set方法
         */
        private void processAllMethod(StringBuffer sb) {
            for (int i = 0; i < colNames.length; i++) {
                sb.append("\tpublic void set" + initCap(colNames[i]) + "(" + sqlType2JavaType(colTypes[i]) + " "
                        + colNames[i] + "){\r\n");
                sb.append("\t\tthis." + colNames[i] + "=" + colNames[i] + ";\r\n");
                sb.append("\t}\r\n");
                sb.append("\tpublic " + sqlType2JavaType(colTypes[i]) + " get" + initCap(colNames[i]) + "(){\r\n");
                sb.append("\t\treturn " + colNames[i] + ";\r\n");
                sb.append("\t}\r\n");
            }
        }
    
        /**
         * @param str 传入字符串
         * @return
         * @description 将传入字符串的首字母转成大写
         */
        private String initCap(String str) {
            char[] ch = str.toCharArray();
            if (ch[0] >= 'a' && ch[0] <= 'z')
                ch[0] = (char) (ch[0] - 32);
            return new String(ch);
        }
    
        /**
          * 功能:下划线命名转驼峰命名
         * @param s
         * @param fistCharToUpperCase 首字母是否大写
         * @author 呐喊
         * @return
         */
        private String under2camel(String s,boolean fistCharToUpperCase) {
           String separator = "_";
            String under="";
            s = s.toLowerCase().replace(separator, " ");
            String sarr[]=s.split(" ");
            for(int i=0;i<sarr.length;i++)
            {
                String w=sarr[i].substring(0,1).toUpperCase()+sarr[i].substring(1);
                under +=w;
            }
            if(!fistCharToUpperCase) {
                under = under.substring(0,1).toLowerCase()+under.substring(1);
            }
            return under;
        }
    
        /**
         * @return
         * @description 查找sql字段类型所对应的Java类型
         */
        private String sqlType2JavaType(String sqlType) {
            if (sqlType.equalsIgnoreCase("bit")) {
                return "boolean";
            } else if (sqlType.equalsIgnoreCase("tinyint")) {
                return "byte";
            } else if (sqlType.equalsIgnoreCase("smallint")) {
                return "short";
            } else if (sqlType.equalsIgnoreCase("int")) {
                return "int";
            } else if (sqlType.equalsIgnoreCase("bigint")) {
                return "long";
            } else if (sqlType.equalsIgnoreCase("float")) {
                return "float";
            } else if (sqlType.equalsIgnoreCase("numeric")
                    || sqlType.equalsIgnoreCase("real") || sqlType.equalsIgnoreCase("money")
                    || sqlType.equalsIgnoreCase("smallmoney")) {
                return "double";
            } else if (sqlType.equalsIgnoreCase("varchar") || sqlType.equalsIgnoreCase("char")
                    || sqlType.equalsIgnoreCase("nvarchar") || sqlType.equalsIgnoreCase("nchar")
                    || sqlType.equalsIgnoreCase("text")|| sqlType.equalsIgnoreCase("longtext")) {
                return "String";
            } else if (sqlType.equalsIgnoreCase("datetime")) {
                return "Date";
            } else if (sqlType.equalsIgnoreCase("image")) {
                return "Blod";
             }else if (sqlType.equalsIgnoreCase("decimal")) {
                 return "BigDecimal";
             }
            return null;
        }
        /**
         * 功能:获取并创建实体所在的路径目录
         * @return
         */
        private static String pkgDirName() {
           String dirName = basePath + "/src/" + packageOutPath.replace(".", "/");
           File dir = new File(dirName);
           if (!dir.exists()) {dir.mkdirs();System.out.println("mkdirs dir 【" + dirName + "】");}
           return dirName;
        }
        /**
         * 生成EntityHelper
         */
        private void EntityHelper() {
            String dirName = MySQLGeneratorEntityUtil.pkgDirName();
            String javaPath = dirName + "/EntityHelper.java";
           try {
               StringBuffer sb = new StringBuffer();
              sb.append("package " + packageOutPath + ";\r\n");
              sb.append("\r\n");
              sb.append("public abstract class EntityHelper{\r\n\r\n");
              sb.append("\tpublic abstract String getPrimaryKey();\r\n");
              sb.append("\r\n");
              sb.append("}\r\n");
                FileWriter fw = new FileWriter(javaPath);
                PrintWriter pw = new PrintWriter(fw);
                pw.println(sb.toString());
              pw.flush();
              if (pw != null){pw.close();}
              System.out.println("create class 【EntityHelper】");
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        /**
         * @description 生成方法
         */
        private void generate() throws Exception {
            //与数据库的连接
            Connection con;
            PreparedStatement pStemt = null;
            Class.forName(DRIVER);
            con = DriverManager.getConnection(URL, NAME, PASS);
            System.out.println("connect database success..."+con);
            //获取数据库的元数据
            DatabaseMetaData db = con.getMetaData();
            //是否有指定生成表,有指定则直接用指定表,没有则全表生成
            List<String> tableNames = new ArrayList<>();
            if (generateTables == null) {
                //从元数据中获取到所有的表名
                ResultSet rs = db.getTables(null, null, null, new String[] { "TABLE" });
                while (rs.next()) tableNames.add(rs.getString(3));
            } else {
                for (String tableName : generateTables) tableNames.add(tableName);
            }
           if(needEntityHelper) {
             EntityHelper();
            }
            String tableSql;
            PrintWriter pw = null;
            for (int j = 0; j < tableNames.size(); j++) {
                tableName = tableNames.get(j);
                tableSql = SQL + tableName;
                pStemt = con.prepareStatement(tableSql);
                ResultSetMetaData rsmd = pStemt.getMetaData();
                ResultSet rsk = con.getMetaData().getPrimaryKeys(con.getCatalog().toLowerCase(), null, tableName);
                if (rsk.next()) {
                 String primaryKey = rsk.getString("COLUMN_NAME");
                 pk=primaryKey;
                   }
                int size = rsmd.getColumnCount();
                colNames = new String[size];
                colTypes = new String[size];
                colSizes = new int[size];
                //获取所需的信息
                for (int i = 0; i < size; i++) {
                    colNames[i] = rsmd.getColumnName(i + 1);
                    colTypes[i] = rsmd.getColumnTypeName(i + 1);
                    if (colTypes[i].equalsIgnoreCase("datetime"))
                        needUtil = true;
                    if (colTypes[i].equalsIgnoreCase("image") || colTypes[i].equalsIgnoreCase("text"))
                        needSql = true;
                    colSizes[i] = rsmd.getColumnDisplaySize(i + 1);
                }
                //获取字段注释
              ResultSet rsComment = pStemt.executeQuery("show full columns from " + tableName);
              while (rsComment.next()) {
                    colNamesComment.put(rsComment.getString("Field"), rsComment.getString("Comment"));
                }
              //解析生成实体java文件的所有内容
            String content = parse();
              //输出生成文件
            String dirName = MySQLGeneratorEntityUtil.pkgDirName();
            String javaPath = dirName + "/" + under2camel(tableName, true) + ".java";
            FileWriter fw = new FileWriter(javaPath);
            pw = new PrintWriter(fw);
            pw.println(content);
            pw.flush();
            System.out.println("create class 【" + tableName + "】");
            }
            if (pw != null)
                pw.close();
        }
    
        public static void main(String[] args) {
    
            MySQLGeneratorEntityUtil instance = new MySQLGeneratorEntityUtil();
            //instance.basePath=""; //指定生成的位置,默认是当前工程
            try {
                  instance.generate();
                System.out.println("generate Entity to classes successful!");
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    
    
    1. idea 端口1099改为其他的,无法进入debug模式
      https://www.cnblogs.com/LeoBoy/p/5798947.html
      mac关闭端口 https://blog.csdn.net/aaaaazq/article/details/80928175
    2. session

    本文由博客一文多发平台 OpenWrite 发布!

    相关文章

      网友评论

          本文标题:ssm学习笔记精选(1)

          本文链接:https://www.haomeiwen.com/subject/hflzfktx.html