groovy listmap拍平成map flattenedMap重名的key都被覆盖了怎么办

如果在拍平过程中遇到重名的key，可以采取以下几种处理方式：

1. 保留最后一个值：当遇到重名的key时，只保留最后一个值，其他重名的值都被覆盖。

def list = [
    [name: "John", age: 25],
    [name: "Alice", age: 30],
    [name: "John", age: 35]
]

def flattenedMap = [:]
list.each { map ->
    map.each { key, value ->
        flattenedMap[key] = value
    }
}

println flattenedMap

输出结果:

[name:John, age:35]

2. 保留所有值：当遇到重名的key时，将所有的值保存到一个列表中。

def list = [
    [name: "John", age: 25],
    [name: "Alice", age: 30],
    [name: "John", age: 35]
]

def flattenedMap = [:]
list.each { map ->
    map.each { key, value ->
        if (flattenedMap.containsKey(key)) {
            flattenedMap[key] << value
        } else {
            flattenedMap[key] = [value]
        }
    }
}

println flattenedMap

输出结果:

[name:[John, Alice], age:[25, 30, 35]]

3. 保留所有值，并使用索引作为后缀：当遇到重名的key时，将所有的值保存到一个列表中，并使用索引作为后缀来区分不同的值。

def list = [
    [name: "John", age: 25],
    [name: "Alice", age: 30],
    [name: "John", age: 35]
]

def flattenedMap = [:]
list.eachWithIndex { map, index ->
    map.each { key, value ->
        if (flattenedMap.containsKey(key)) {
            flattenedMap[key + index] = value
        } else {
            flattenedMap[key] = value
        }
    }
}

println flattenedMap

输出结果:

[name:John, age:25, name1:Alice, age1:30, name2:John, age2:35]

你可以根据具体的需求选择适合的处理方式