使用idea插件生成jpa实体类

• 打开视图
  • view -> Tool Windows -> Database
• 新建mysql数据源，配置数据库信息
  • 点击+ -> Data source -> MySQL
  • 
• 在项目引入必要maven依赖

  • 
    
        org.springframework.boot
        spring-boot-starter-data-jpa
    
    
    
        mysql
        mysql-connector-java
    
    
    
        org.projectlombok
        lombok
        true
    

• 建立存放实体的包
  • 
• 编写逆向工程的脚本文件Generate POJOs.groovy
  • 在database视图区域任意地方右键，点击 Scripted Extensions -> Go to Scripts Directory
  • 
  • 编辑Generate POJOs.groovy，代码如下：

  • import com.intellij.database.model.DasTable
    import com.intellij.database.model.ObjectKind
    import com.intellij.database.util.Case
    import com.intellij.database.util.DasUtil
    import java.io.*
    import java.text.SimpleDateFormat
    
    /*
     * Available context bindings:
     *   SELECTION   Iterable
     *   PROJECT     project
     *   FILES       files helper
     */
    packageName = ""
    typeMapping = [
            (~/(?i)tinyint|smallint|mediumint/)      : "Integer",
            (~/(?i)int/)                             : "Long",
            (~/(?i)bool|bit/)                        : "Boolean",
            (~/(?i)float|double|decimal|real/)       : "Double",
            (~/(?i)datetime|timestamp|date|time/)    : "Date",
            (~/(?i)blob|binary|bfile|clob|raw|image/): "InputStream",
            (~/(?i)/)                                : "String"
    ]
    
    
    FILES.chooseDirectoryAndSave("Choose directory", "Choose where to store generated files") { dir ->
      SELECTION.filter { it instanceof DasTable && it.getKind() == ObjectKind.TABLE }.each { generate(it, dir) }
    }
    
    def generate(table, dir) {
      def className = javaClassName(table.getName(), true)
      def fields = calcFields(table)
      packageName = getPackageName(dir)
      PrintWriter printWriter = new PrintWriter(new OutputStreamWriter(new FileOutputStream(new File(dir, className + ".java")), "UTF-8"))
      printWriter.withPrintWriter {out -> generate(out, className, fields,table)}
    
    //    new File(dir, className + ".java").withPrintWriter { out -> generate(out, className, fields,table) }
    }
    
    // 获取包所在文件夹路径
    def getPackageName(dir) {
      return dir.toString().replaceAll("\\\\", ".").replaceAll("/", ".").replaceAll("^.*src(\\.main\\.java\\.)?", "") + ";"
    }
    
    def generate(out, className, fields,table) {
      out.println "package $packageName"
      out.println ""
      out.println "import javax.persistence.Column;"
      out.println "import javax.persistence.Entity;"
      out.println "import javax.persistence.Table;"
      out.println "import java.io.Serializable;"
      out.println "import lombok.Data;"
    
      Set types = new HashSet()
    
      fields.each() {
        types.add(it.type)
      }
    
      if (types.contains("Date")) {
        out.println "import java.util.Date;"
      }
    
      if (types.contains("InputStream")) {
        out.println "import java.io.InputStream;"
      }
      out.println ""
      out.println "/**\n" +
              " * @Title "+ table.getName()+" \n" +
              " * @Description  \n" +
              " * @author tlj \n" +
              " * @Date "+ new SimpleDateFormat("yyyy-MM-dd").format(new Date()) + " \n" +
              " */"
      out.println ""
      out.println "@Entity"
      out.println "@Table ( name =\""+table.getName() +"\" )"
      out.println "@Data"
      out.println "public class $className  implements Serializable {"
      out.println ""
      out.println genSerialID()
      fields.each() {
        out.println ""
        // 输出注释
        if (isNotEmpty(it.commoent)) {
          out.println "\t/**"
          out.println "\t * ${it.commoent.toString()}"
          out.println "\t */"
        }
    
        if (it.annos != "") out.println "   ${it.annos.replace("[@Id]", "")}"
    
        // 输出成员变量
        out.println "\tprivate ${it.type} ${it.name};"
      }
    
      out.println ""
      out.println "}"
    }
    
    def calcFields(table) {
      DasUtil.getColumns(table).reduce([]) { fields, col ->
        def spec = Case.LOWER.apply(col.getDataType().getSpecification())
        def typeStr = typeMapping.find { p, t -> p.matcher(spec).find() }.value
        def comm =[
                colName : col.getName(),
                name :  javaName(col.getName(), false),
                type : typeStr,
                commoent: col.getComment(),
                annos: "\t@Column(name = \""+col.getName()+"\" , columnDefinition = \""+spec+" DEFAULT NULL"+ " COMMENT \'"+col.getComment()+"\'\")"]
        if("id".equals(Case.LOWER.apply(col.getName())))
          comm.annos +=["@Id"]
        fields += [comm]
      }
    }
    
    // 处理类名（这里是因为我的表都是以t_命名的，所以需要处理去掉生成类名时的开头的T，
    // 如果你不需要那么请查找用到了 javaClassName这个方法的地方修改为 javaName 即可）
    def javaClassName(str, capitalize) {
      def s = com.intellij.psi.codeStyle.NameUtil.splitNameIntoWords(str)
              .collect { Case.LOWER.apply(it).capitalize() }
              .join("")
              .replaceAll(/[^\p{javaJavaIdentifierPart}[_]]/, "_")
      // 去除开头的T  http://developer.51cto.com/art/200906/129168.htm
      s = s[1..s.size() - 1]
      capitalize || s.length() == 1? s : Case.LOWER.apply(s[0]) + s[1..-1]
    }
    
    def javaName(str, capitalize) {
    //    def s = str.split(/(?<=[^\p{IsLetter}])/).collect { Case.LOWER.apply(it).capitalize() }
    //            .join("").replaceAll(/[^\p{javaJavaIdentifierPart}]/, "_")
    //    capitalize || s.length() == 1? s : Case.LOWER.apply(s[0]) + s[1..-1]
      def s = com.intellij.psi.codeStyle.NameUtil.splitNameIntoWords(str)
              .collect { Case.LOWER.apply(it).capitalize() }
              .join("")
              .replaceAll(/[^\p{javaJavaIdentifierPart}[_]]/, "_")
      capitalize || s.length() == 1? s : Case.LOWER.apply(s[0]) + s[1..-1]
    }
    
    def isNotEmpty(content) {
      return content != null && content.toString().trim().length() > 0
    }
    
    static String changeStyle(String str, boolean toCamel){
      if(!str || str.size() <= 1)
        return str
    
      if(toCamel){
        String r = str.toLowerCase().split('_').collect{cc -> Case.LOWER.apply(cc).capitalize()}.join('')
        return r[0].toLowerCase() + r[1..-1]
      }else{
        str = str[0].toLowerCase() + str[1..-1]
        return str.collect{cc -> ((char)cc).isUpperCase() ? '_' + cc.toLowerCase() : cc}.join('')
      }
    }
    
    static String genSerialID()
    {
      return "\tprivate static final long serialVersionUID =  "+Math.abs(new Random().nextLong())+"L;"
    }

     

• 生成实体java类
  • 选中数据库表：
  • 
  • 在database视图区域任意地方右键，然后Scripted Extensions ->Generate POJOs.groovy
  • 
  • 选择实体存放路径
  • 
  • 生成目标实体
  •