版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/huanghuangjin/article/details/82260733
list
//def list = new ArrayList() // java
def list = [1, 2, 3, 4, 5] // 定义list
println list.class // class java.util.ArrayList
println list.size() // 5
def arr1 = [1, 2, 3] as int[] // 使用 as 关键字将list转换为数组
int[] arr2 = [1, 3, 4] // 定义数组
def sortList = [6, -3, 9, 2, -7, 1, 5]
Comparator mc = { // 自定义排序规则，按绝对值大小排序
a, b -> a==b ? 0 : (Math.abs(a)<Math.abs(b) ? -1 : 1)
}
Collections.sort(sortList, mc)
println sortList // [1, 2, -3, 5, 6, -7, 9]
def sort = [6, -3, 9, 2, -7, 1, 5]
sort.sort { // sort的闭包可以有很多种形式，参看源码
// a, b -> a==b ? 0 : (Math.abs(a)<Math.abs(b) ? -1 : 1) // 按绝对值大小排序， [1, 2, -3, 5, 6, -7, 9]
it -> return it // 按其本身值大小排序， [-7, -3, 1, 2, 5, 6, 9]
}
println sort
def fs = [6, -3, 9, 2, -7, 1, 5]
println fs.find { it%2==0 } // 6
println fs.findAll { it%2==0 } // [6, 2]
println fs.any { it%2==0 } // true
println fs.every { it%2==0 } // false
println fs.min() { Math.abs(it) } // 1 ， 返回绝对值最小的元素
println fs.max() // 9 ， 也可以使用闭包
println fs.count { it%2==0 } // 2 ， 统计，符合闭包中的规则的元素的个数
map
def colors = [red: 'ff0000', 'green': '00ff00', blue: '0000ff'] as Hashtable // 定义map，key值建议使用单引号的字符串，如果key值没加引号，编译其会自动添加
println colors.getClass() // class java.util.Hashtable ， 默认为 java.util.LinkedHashMap ， 使用 colors.class 表示获取map中key为class的value值
println colors['red'] // ff0000 ， 获取map中key为red的值
println colors.red // ff0000 ， 获取map中key为red的值
colors.yellow = 'ffff00' // 当map中的key没有yellow时，添加，有yellow时，修改对应的value值
colors.complex = [a:1, b:2] // 给map添加map， map中可以添加任意类型的对象
println colors // [red:ff0000, green:00ff00, blue:0000ff, yellow:ffff00, complex:[a:1, b:2]]
def students = [
1: [number: '0001', name: 'Bob',
score : 55, sex: 'male'],
2: [number: '0002', name: 'Johnny',
score : 62, sex: 'female'],
3: [number: '0003', name: 'Claire',
score : 73, sex: 'female'],
4: [number: '0004', name: 'Amy',
score : 66, sex: 'male']
]
students.each { // 遍历
// key is 1, value is [number:0001, name:Bob, score:55, sex:male]
// key is 2, value is [number:0002, name:Johnny, score:62, sex:female]
// key is 3, value is [number:0003, name:Claire, score:73, sex:female]
// key is 4, value is [number:0004, name:Amy, score:66, sex:male]
def student -> println "key is $student.key," + " value is $student.value"
}
students.eachWithIndex { // 遍历，带下标
// index is 0, key is 1, value is [number:0001, name:Bob, score:55, sex:male]
// index is 1, key is 2, value is [number:0002, name:Johnny, score:62, sex:female]
// index is 2, key is 3, value is [number:0003, name:Claire, score:73, sex:female]
// index is 3, key is 4, value is [number:0004, name:Amy, score:66, sex:male]
def student, int index -> println "index is $index," + " key is $student.key," + " value is $student.value"
}
students.each { // 遍历，闭包参数直接传 key value ， 也有 eachWithIndex 带下标
// key is 1, value is [number:0001, name:Bob, score:55, sex:male]
// key is 2, value is [number:0002, name:Johnny, score:62, sex:female]
// key is 3, value is [number:0003, name:Claire, score:73, sex:female]
// key is 4, value is [number:0004, name:Amy, score:66, sex:male]
key, value -> println "key is $key," + " value is $value"
}
println students.find { it.value.score >= 60 } // 2={number=0002, name=Johnny, score=62, sex=female} ， 查找第一个score大于等于60的元素
println students.findAll { it.value.score >= 66 } // [3:[number:0003, name:Claire, score:73, sex:female], 4:[number:0004, name:Amy, score:66, sex:male]]
println students.count { it.value.score>=60 && it.value.sex=='male' } // 1
println students.findAll { it.value.score >= 66 }.collect { it.value.name } // [Claire, Amy] ， 查找score大于等于66的学生的name
def group = students.groupBy { it.value.score>=60 ? "及格" : "不及格" } // 分组
// [不及格:[1:[number:0001, name:Bob, score:55, sex:male]], 及格:[2:[number:0002, name:Johnny, score:62, sex:female], 3:[number:0003, name:Claire, score:73, sex:female], 4:[number:0004, name:Amy, score:66, sex:male]]]
println group.toMapString()
def sort = students.sort { // 排序，与list不一样的地方是，map的sort返回的是新的排好序的map，是不改变students值的，而list是改变原list的值，并不返回list
def student1, def student2 ->
Number score1 = student1.value.score // Number 可以表示整型，也可以表示浮点型
Number score2 = student2.value.score
return score1 == score2 ? 0 : score1 < score2 ? -1 : 1
}
// [1:[number:0001, name:Bob, score:55, sex:male], 2:[number:0002, name:Johnny, score:62, sex:female], 4:[number:0004, name:Amy, score:66, sex:male], 3:[number:0003, name:Claire, score:73, sex:female]]
println sort.toMapString()
range
def range = 1..10 // range本质就是一个list类
println range[1] // 2 ， 获取下标1的值
println range.contains(10) // true ， range中是否包含10
println range.from // 1 ， 其实值
println range.to // 10 ， 终点值
range.each { // 遍历
println it
}
def getGrade(Number number) {
def ret
switch (number) {
case 0..<60: ret = '不及格'; break // <60 表示range不取60
case 60..<70: ret = '及格'; break
case 70..<80: ret = '良好'; break
case 80..100: ret = '优秀'; break
}
return ret
}
println getGrade(75) // 良好