使用idea根據數據庫表來生成對應的實體類

1. 打開idea，找到database，選擇想要連接的數據庫類型

2. 輸入數據庫連接信息，點擊test connection ，出現Successful, 然後點擊Apply, OK
   
   3, idea右邊會出現數據庫的表，
   
   4，選中一張表右鍵，進入生成實體類的腳步目錄
   
   5，進入到這裏，idea左邊的目錄，點擊進入groovy腳本文件，修改成你想要的生成格式
   
   6，下面代碼就是我的groovy腳本的內容，可以拷貝粘貼

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


packageName = ""
typeMapping = [
        (~/(?i)tinyint|smallint|mediumint/)      : "Integer",
        (~/(?i)int/)                             : "Long",
        (~/(?i)decimal/)                         : "BigDecimal",
        (~/(?i)bool|bit/)                        : "Boolean",
        (~/(?i)float|double|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 = javaName(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) }
}

// 獲取包所在文件夾路徑
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 java.io.Serializable;"
  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" +
          " * @Description  \n" +
          " * @Author  guoyingjie\n" +
          " * @Date "+ new SimpleDateFormat("yyyy-MM-dd").format(new Date()) + " \n" +
          " */"
  out.println ""
  out.println "@Table(name =\""+table.getName() +"\")"
  out.println "public class $className  implements Serializable {"
  out.println ""
  out.println genSerialID()
  fields.each() {
    out.println ""
    // 輸出註釋
    if (isNotEmpty(it.commoent)) {
      out.println "\t/**"
      out.println "\t * ${it.commoent.toString()}"
      out.println "\t */"
    }

    if (it.annos != "") out.println "   ${it.annos.replace("[seqName]", table.getName())}"

    // 輸出成員變量
    out.println "\tprivate ${it.type} ${it.name};"
  }

  // 輸出get/set方法
  fields.each() {
    out.println ""
    out.println "\tpublic ${it.type} get${it.name.capitalize()}() {"
    out.println "\t\treturn this.${it.name};"
    out.println "\t}"
    out.println ""

    out.println "\tpublic void set${it.name.capitalize()}(${it.type} ${it.name}) {"
    out.println "\t\tthis.${it.name} = ${it.name};"
    out.println "\t}"
  }
  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: ""
    ]
    if("id".equals(Case.LOWER.apply(col.getName())))
      comm.annos += "@Fields(isPrimaryKey=true,sequenceName=\"seq_[seqName]_id\")"
    fields += [comm]
  }
}

// 處理類名（這裏是因爲我的表都是以t_命名的，所以需要處理去掉生成類名時的開頭的T，
// 如果你不需要那麼請查找用到了 javaClassName這個方法的地方修改爲 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}[_]]/, "_")
  // 去除開頭的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;"
}

7，再次選擇表，然後生成pojo類，點擊scripted Extensions下面的第一個選項，注意是第一個選項

8,點擊之後會彈出一個彈框用來選擇文件所要存放的目錄，建議選擇項目的pojo類的目錄，選完open即可，然後去你的pojo目錄下就能找到你想要生成的表對應的實體類。