這是一個天真的例子,使用了一些Justin Piper的代碼。通讀我發佈的 以及列表JDK的API。你肯定能夠做出更有效的方法。 這段代碼應該給你一個關於groovy是如何工作的,以及閉包可以做什麼的好主意。
class File {
String name
int type
int revision
String toString() { "File(name: $name; type: $type; revision: $revision)" }
}
def files = [
new File(name: 'First Type2', type: 2, revision: 0),
new File(name: 'First Type0', type: 0, revision: 1),
new File(name: 'First Type1', type: 1, revision: 1),
new File(name: 'Second Type0', type: 0, revision: 0),
new File(name: 'Second Type1', type: 2, revision: 1),
new File(name: 'Second Type2', type: 1, revision: 1),
]
//This will hold the final set of files according to the logic in the next each()
def selectedFiles = [:]
files.each { file ->
//Overwrite the value associated with the key, which is the type depending on the logic - we only keep 1 of each type
if(selectedFiles[file.type]){
if(selectedFiles[file.type].revision < file.revision){
selectedFiles[file.type] = file
}
}
else{
//This type never existed, so just write the file as the value
selectedFiles[file.type] = file
}
}
selectedFiles.each { type, file ->
println(file)
}
你能舉個例子嗎 – n92