I have list with Versions (Strings), I want to make List of List for version of every release
List<List<String>> releases = new ArrayList<List<String>>();
def list = ["7.5.9", "7.5.8", "7.5.7", "7.5.6", "7.5.5", "7.5.4", "7.5.3", "7.5.2", "7.5.1", "7.5.0", "6.5.1", "6.5.0"];
I want to have collection for every release First list of versions 1.0.0, 1.0.1, 1.0.2, Second list of versions 1.5.0, 1.5.1 Third list of versions 2.0.0 ... and so on for every release
Since the release versions have two digits, the input list may be grouped by the prefix (thus getting a map of String, List<String>) using Collectors.groupingBy and then the list of the versions is sorted using Collectors.collectingAndThen:
List<List<String>> versions = new ArrayList<>(
list
.stream()
.collect(Collectors.groupingBy(
str -> str.substring(0, str.lastIndexOf('.')),
Collectors.collectingAndThen(
Collectors.toList(),
(List<String> lst) -> { lst.sort(String::compareTo); return lst; }
)
))
.values() // Collection<List<String>>
);
versions.forEach(System.out::println);
Output:
[1.0.0, 1.0.1, 1.0.2]
[2.0.0]
[3.0.0, 3.0.1]
[1.5.0, 1.5.1]
[2.5.0]
[3.5.0]
The code above assumes the format of the release part in the version always has at least two dots (major and minor versions).
If some versions may not comply with the initial format (e.g., there are 0.1 or 1.0.2.1), the following grouping condition should work fine:
str -> str.substring(0, str.indexOf('.', str.indexOf('.') + 1) + 1), - the release prefix is assumed to contain at least 1 dot . and at most two dots.
Example Groovy implementation:
def list = ["3.5.0", "3.0.1", "3.0.0", "2.5.0", "2.0.0", "1.5.1", "1.5.0", "1.0.2", "1.0.1", "1.0.0"]
def versions = new ArrayList<> (list.groupBy {
it.substring(0, it.lastIndexOf('.'))
}.values())
.each { it.sort() }
versions.each {println it }
Output:
[3.5.0]
[3.0.0, 3.0.1]
[2.5.0]
[2.0.0]
[1.5.0, 1.5.1]
[1.0.0, 1.0.1, 1.0.2]
Update
The following Groovy code fixes sorting issues and also removes the highest version as well as the empty results:
def list = ["3.5.0", "3.0.1", "3.0.0", "2.5.0", "2.0.0", "1.5.1", "1.5.0", "1.0.1", "1.0.0",
"1.0.10", "1.0.11", "1.0.2", "1.0.3", "1.0.4", "1.0.5", "1.0.6", "1.0.7", "1.0.8", "1.0.9"]
def versions = new ArrayList<> (
list
.sort() // sort initial list
.groupBy {
it.substring(0, it.lastIndexOf('.'))
}.values()
)
.each { it.sort{ a,b -> Integer.compare(
Integer.parseInt(a.substring(a.lastIndexOf('.') + 1)),
Integer.parseInt(b.substring(b.lastIndexOf('.') + 1))
)}.removeAt(it.size() - 1) }
versions.removeIf { it.empty } // remove empty sublists if any found
versions.each {println it }
Output
[1.0.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.0.6, 1.0.7, 1.0.8, 1.0.9, 1.0.10]
[1.5.0]
[3.0.0]
Try this.
public static void main(String[] args) {
List<String> list = new ArrayList<String>();
list.add("3.5.0");
list.add("3.0.1");
list.add("3.0.0");
list.add("2.5.0");
list.add("2.0.0");
list.add("1.5.1");
list.add("1.5.0");
list.add("1.0.2");
list.add("1.0.1");
list.add("1.0.0");
Collections.sort(list);
Map<String, List<String>> map = new TreeMap<>();
for (String e : list)
map.computeIfAbsent(e.replaceFirst("\\.\\d+$", ""), k -> new ArrayList<>()).add(e);
List<List<String>> releases = new ArrayList<>(map.values());
System.out.println(releases);
}
output:
[[1.0.0, 1.0.1, 1.0.2], [1.5.0, 1.5.1], [2.0.0], [2.5.0], [3.0.0, 3.0.1], [3.5.0]]
Use streams:
List<List<String>> versions =
list.stream()
.collect(Collectors.groupingBy(/* a function which extracts the version */))
.values() /* gives you a Collection<List<String>>, stop here if you don't need it as an actual List */
.stream()
.collect(Collectors.toList());
An example of "a function which extracts the version" for the values shown could be:
value -> value.substring(0, value.lastIndexOf('.'))
Down below is a pure idiomatic Groovy version w/o Java streams and other strange constructs:
def list = ["7.5.9", "7.5.8", "7.5.7", "7.5.6", "7.5.5", "7.5.4", "7.5.3", "7.5.2", "7.5.1", "7.5.0", "6.5.1", "6.5.0"]
def collector = {
List asInts = it.split( /\./ )*.toInteger()
[ sum:asInts.reverse().withIndex().collect{ v, ix -> 10.power( ix ) * v }.sum(), major:asInts[ 0 ], original:it ]
}
def listOfSublists = list.collect collector sort{ it.sum } groupBy{ it.major } values()*.collect{ it.original }
assert listOfSublists.toString() == '[[6.5.0, 6.5.1], [7.5.0, 7.5.1, 7.5.2, 7.5.3, 7.5.4, 7.5.5, 7.5.6, 7.5.7, 7.5.8, 7.5.9]]'
