//遍历文件内容
def file=new File('../../hello-groovy.iml')
file.eachLine {

line->println( line)
   /* <?xml version="1.0" encoding="UTF-8"?>
    <module type="JAVA_MODULE" version="4">
    <component name="NewModuleRootManager" inherit-compiler-output="true">
    <exclude-output />
    <content url="file://$MODULE_DIR$">
    <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
    </content>
    <orderEntry type="inheritedJdk" />
    <orderEntry type="sourceFolder" forTests="false" />
    <orderEntry type="library" name="groovy-2.4.15" level="application" />
    </component>
    </module>*/

}
//获取文件的内容
def text=file.getText()
println(text)
/* <?xml version="1.0" encoding="UTF-8"?>

    <module type="JAVA_MODULE" version="4">
    <component name="NewModuleRootManager" inherit-compiler-output="true">
    <exclude-output />
    <content url="file://$MODULE_DIR$">
    <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
    </content>
    <orderEntry type="inheritedJdk" />
    <orderEntry type="sourceFolder" forTests="false" />
    <orderEntry type="library" name="groovy-2.4.15" level="application" />
    </component>
    </module>*/

//获取文件另一种方式,按行读取,返回一个list集合
def result=file.readLines()
println(result.toListString())
//[<?xml version="1.0" encoding="UTF-8"?>, <module type="JAVA_MODULE" version="4">,
// <component name="NewModuleRootManager" inherit-compiler-output="true">,
// <exclude-output />, <content url="file://$MODULE_DIR$">,
// <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />,
// </content>, <orderEntry type="inheritedJdk" />,
// <orderEntry type="sourceFolder" forTests="false" />,
// <orderEntry type="library" name="groovy-2.4.15" level="application" />,
// </component>, </module>]

//获取文件部分内容(前20个字符)
def reader=file.withReader {

reader->char [] buffer=new char[20]
    reader.read(buffer)
    buffer

}
println(reader)//<?xml version="1.0"
//写文件 def writer=file.withWriter{闭包}
//文件拷贝,groovy会自己关闭流
def results=copy('../../hello-groovy.iml','../../hello-groovy32.iml')
println(results)//true or false
def copy(String sourcePath,String destationPath){

try{    //创建目标文件
    def desFile=new File(destationPath)    if(!desFile.exists()){
        desFile.createNewFile()
    }    //开始拷贝
    new File(sourcePath).withReader {
        reader->def lines=reader.readLines()
            desFile.withWriter {
                writer->
                    lines.each {
                        line->writer.append(line+'\r\n')
                    }
            }
    }    return  true}catch (Exception e){

}return false

}
//对象的读写
ApplicationManager.init()
def person=PersonManager.createPerson('li',34)
def result3=saveObject(person,'../../person.txt')

def result4=(Person)readObject('../../person.txt')
println("${result4.name}:::${result4.age}")
//保存对象
def saveObject(Object obj,String path){

try{    //目标文件创建
    def desFile=new File(path)    if(!desFile.exists()){
        desFile.createNewFile()
    }    //开始写object
    desFile.withObjectOutputStream {
        out->out.writeObject(obj)
    }    return  true}catch (Exception e){

}return false

}
//读取对象
def readObject(String path){

def obj=nulltry{
    def desFile=new File(path)    if(!desFile.exists()|| desFile==null)return  null
    desFile.withObjectInputStream {input ->
        obj=input.readObject()
    }

}catch (Exception e){

}return obj

}

原文链接：http://www.apkbus.com/blog-953329-77640.html