groovy读取文件

读取csv文件

def text = new File("source.csv").text
assert text instanceof String
println text

 

逐行读取csv文件

 

def file = new File("D:\\tool\\api2direct\\api2direct\\sourceCopy.csv")
assert file.name == 'sourceCopy.csv'
assert file.path == 'D:\\tool\\api2direct\\api2direct\\sourceCopy.csv'
assert file.isAbsolute()
assert file.parent == 'D:\\tool\\api2direct\\api2direct'

file.eachLine{println it}
file.eachLine('GB2312', 3) {str, no ->
   println no
   println str
}

 

对csv文件的每一行内容进行处理

def file = new File("D:\\tool\\api2direct\\api2direct\\sourceCopy.csv")
file.splitEachLine(',') {println it}

def listLine = file.readLines()
listLine.each{
  println it.toUpperCase()
}

listLine.filterLine{str ->
   if(str.contains('RR01S'))
       str
}.writerTo(new PrintWriter(System.out))

 

解析Properties文件

 

/*configure.properties
name=emma
age=26
*/
//读取
def props = new Properties()
new File("configure.properties").withInputStream{stream ->
   props.load(stream)
}

assert props['name'] == 'emma'
assert props['age'] instanceof String
assert props instanceof Map

//通过ConfigSlurper object对象来访问
def config = new ConfigSlurper().pares(props)
assert config.name == 'emma'

 

 更简洁的方式访问，但属性的值若是字符串，需加上引号

/*configure.properties
name="emma"
age=26
*/

//读取
def config = new ConfigSlurper().parse(new File("configure.properties").toURL())

assert config.name == 'emma'
assert config.age instanceof Integer

 

 

 

读取groovy文件

 

/*message.groovy
capacity {
  created="x"
  modified="y"
}
*/
//代码如下
def config = new ConfigSlurper().parse(new File("message.groovy").toURL)
assert config.capacity.created == 'x'

 

 访问目录

def dir = new File("D:\\个人代码\\groovy")
if(dir.isDirectory()) {
    dir.eachFileRecurse {file ->
         println file
    }
}

dir.eachFileMatch(~/.*\.txt/) {file ->
    println file.name
}

 

写入文件

def writeFile(fileName) {
     def file = new File(fileName)
     if(file.exists())
          file.delete()
     def printWriter = file.newPrintWriter()
     printWriter.println('The first line')
     printWriter.write('The second line')
     
     printWriter.flush()
     printWriter.close()
}

writeFile('output.txt')

 更简洁的写法

new File('log.txt').withPrintWriter{printWriter ->
    printWriter.println('The first line')
    printWriter.write('The second line')
}

 除了file.newPrintWriter() 可以得到一个 PrintWriter，类似方法还有file.newInputStream()、file.newObjectInputStream()等