idea自动生成bean实体对象

idea软件自身提供了方法用于实体对象的生成，可借助此方法来进行无需单独安装插件。在Database窗口中点击要操作的表右键打开，可看到如下：

 Generate POJOs.groovy文件提供了相关实体生成时展示的内容，我们可根据自身需求再进行调整，比如添加注释、注解、包等内容。

com.intellij.database.util.DasUtil包中会提供很多相关方法，可自行查看。

import com.intellij.database.model.DasTable
import com.intellij.database.util.Case
import com.intellij.database.util.DasUtil



packageName = "com.sample;"
typeMapping = [
  (~/(?i)int/)                      : "long",
  (~/(?i)float|double|decimal|real/): "double",
  (~/(?i)datetime|timestamp/)       : "java.sql.Timestamp",
  (~/(?i)date/)                     : "java.sql.Date",
  (~/(?i)time/)                     : "java.sql.Time",
  (~/(?i)/)                         : "String"
]

FILES.chooseDirectoryAndSave("Choose directory", "Choose where to store generated files") { dir ->
  SELECTION.filter { it instanceof DasTable }.each { generate(it, dir) }
}

def generate(table, dir) {
  def className = javaName(table.getName(), true)
  def fields = calcFields(table)
  new File(dir, className + ".java").withPrintWriter('utf-8') { out -> generate(out, className, fields,table) }
}

def generate(out, className, fields,table) {
  out.println "package $packageName"
  out.println ""
  out.println ""
  out.println "@Data"
  out.println "@Table(name = ""+table.getName()+"")"
  out.println "public class $className {"
  out.println ""
  fields.each() {
      // 输出注释
    if (it.comment!="") {
        out.println "t"
    }
    //添加column注解
    if(it.isPkey){
        out.println "  @Id"
    }
    if (it.annos != "") out.println "  ${it.annos}"
    out.println "  @Column(name = "${it.filed}")"
    out.println "  private ${it.type} ${it.name};"
  }
  out.println ""
  fields.each() {
    out.println ""
    out.println "  public ${it.type} get${it.name.capitalize()}() {"
    out.println "    return ${it.name};"
    out.println "  }"
    out.println ""
    out.println "  public void set${it.name.capitalize()}(${it.type} ${it.name}) {"
    out.println "    this.${it.name} = ${it.name};"
    out.println "  }"
    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
    fields += [[
                 name : javaName(col.getName(), false),
                 type : typeStr,
                 filed: col.getName(),
                    //字段说明,此处采用utf-8无效依然会报错，在上面的输出流中修改
                 comment: (new String(col.getComment().getBytes("utf-8"))),  
                 isPkey: DasUtil.isPrimary(col),
                 annos: ""]]
  }
}

def javaName(str, capitalize) {
  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]
}