是否有比较版本号的标准习语?我不能直接使用String compareTo,因为我还不知道点释放的最大数量是多少。我需要比较版本,并有以下保持正确:

1.0 < 1.1
1.0.1 < 1.1
1.9 < 1.10

当前回答

也许有人会对我的解决方案感兴趣:

class Version private constructor(private val versionString: String) : Comparable<Version> {

    private val major: Int by lazy { versionString.split(".")[0].toInt() }

    private val minor: Int by lazy { versionString.split(".")[1].toInt() }

    private val patch: Int by lazy {
        val splitArray = versionString.split(".")

        if (splitArray.size == 3)
            splitArray[2].toInt()
        else
            0
    }

    override fun compareTo(other: Version): Int {
        return when {
            major > other.major -> 1
            major < other.major -> -1
            minor > other.minor -> 1
            minor < other.minor -> -1
            patch > other.patch -> 1
            patch < other.patch -> -1
            else -> 0
        }
    }

    override fun equals(other: Any?): Boolean {
        if (other == null || other !is Version) return false
        return compareTo(other) == 0
    }

    override fun hashCode(): Int {
        return major * minor * patch
    }

    companion object {
        private fun doesContainsVersion(string: String): Boolean {
            val versionArray = string.split(".")

            return versionArray.size in 2..3
                    && versionArray[0].toIntOrNull() != null
                    && versionArray[1].toIntOrNull() != null
                    && (versionArray.size == 2 || versionArray[2].toIntOrNull() != null)
        }

        fun from(string: String): Version? {
            return if (doesContainsVersion(string)) {
                Version(string)
            } else {
                null
            }
        }
    }
}

用法:

val version1 = Version.from("3.2")
val version2 = Version.from("3.2.1")
version1 <= version2

其他回答

对于我的项目,我使用我的公共版本库https://github.com/raydac/commons-version 它包含两个辅助类-用于解析版本(解析后的版本可以与另一个版本对象进行比较,因为它是可比的)和VersionValidator,它允许检查一些表达式的版本,如!=ide-1.1.1,>idea-1.3.4-SNAPSHOT;<1.2.3

也许有人会对我的解决方案感兴趣:

class Version private constructor(private val versionString: String) : Comparable<Version> {

    private val major: Int by lazy { versionString.split(".")[0].toInt() }

    private val minor: Int by lazy { versionString.split(".")[1].toInt() }

    private val patch: Int by lazy {
        val splitArray = versionString.split(".")

        if (splitArray.size == 3)
            splitArray[2].toInt()
        else
            0
    }

    override fun compareTo(other: Version): Int {
        return when {
            major > other.major -> 1
            major < other.major -> -1
            minor > other.minor -> 1
            minor < other.minor -> -1
            patch > other.patch -> 1
            patch < other.patch -> -1
            else -> 0
        }
    }

    override fun equals(other: Any?): Boolean {
        if (other == null || other !is Version) return false
        return compareTo(other) == 0
    }

    override fun hashCode(): Int {
        return major * minor * patch
    }

    companion object {
        private fun doesContainsVersion(string: String): Boolean {
            val versionArray = string.split(".")

            return versionArray.size in 2..3
                    && versionArray[0].toIntOrNull() != null
                    && versionArray[1].toIntOrNull() != null
                    && (versionArray.size == 2 || versionArray[2].toIntOrNull() != null)
        }

        fun from(string: String): Version? {
            return if (doesContainsVersion(string)) {
                Version(string)
            } else {
                null
            }
        }
    }
}

用法:

val version1 = Version.from("3.2")
val version2 = Version.from("3.2.1")
version1 <= version2

最好的方法是重用现有代码, 使用Maven的ComparableVersion类

优点:

Apache许可证,版本2.0, 测试, 在多个项目中使用(复制),如spring-security-core, jboss等 多个特性 它已经是java.lang。可比的了 只是复制粘贴一个类,没有第三方依赖

不要包含对maven-artifact的依赖项,因为那会拉动各种传递依赖项

基于https://stackoverflow.com/a/27891752/2642478

class Version(private val value: String) : Comparable<Version> {
    private val splitted by lazy { value.split("-").first().split(".").map { it.toIntOrNull() ?: 0 } }

    override fun compareTo(other: Version): Int {
        for (i in 0 until maxOf(splitted.size, other.splitted.size)) {
            val compare = splitted.getOrElse(i) { 0 }.compareTo(other.splitted.getOrElse(i) { 0 })
            if (compare != 0)
                return compare
        }
        return 0
    }
}

你可以用like:

    System.err.println(Version("1.0").compareTo( Version("1.0")))
    System.err.println(Version("1.0") < Version("1.1"))
    System.err.println(Version("1.10") > Version("1.9"))
    System.err.println(Version("1.10.1") > Version("1.10"))
    System.err.println(Version("0.0.1") < Version("1"))

我现在就做了,然后问自己,这对吗?因为我从来没有找到过比我的更干净的解决方案

你只需要像下面这样拆分字符串版本("1.0.0"):

userVersion.split("\\.")

那么你将得到:{"1","0","0"}

现在,用我做过的方法

isUpdateAvailable(userVersion.split("\\."), latestVersionSplit.split("\\."));

方法:

/**
 * Compare two versions
 *
 * @param userVersionSplit   - User string array with major, minor and patch version from user (exemple: {"5", "2", "70"})
 * @param latestVersionSplit - Latest string array with major, minor and patch version from api (example: {"5", "2", "71"})
 * @return true if user version is smaller than latest version
 */
public static boolean isUpdateAvailable(String[] userVersionSplit, String[] latestVersionSplit) {

    try {
        int majorUserVersion = Integer.parseInt(userVersionSplit[0]);
        int minorUserVersion = Integer.parseInt(userVersionSplit[1]);
        int patchUserVersion = Integer.parseInt(userVersionSplit[2]);

        int majorLatestVersion = Integer.parseInt(latestVersionSplit[0]);
        int minorLatestVersion = Integer.parseInt(latestVersionSplit[1]);
        int patchLatestVersion = Integer.parseInt(latestVersionSplit[2]);

        if (majorUserVersion <= majorLatestVersion) {
            if (majorUserVersion < majorLatestVersion) {
                return true;
            } else {
                if (minorUserVersion <= minorLatestVersion) {
                    if (minorUserVersion < minorLatestVersion) {
                        return true;
                    } else {
                        return patchUserVersion < patchLatestVersion;
                    }
                }
            }
        }
    } catch (Exception ignored) {
        // Will be throw only if the versions pattern is different from "x.x.x" format
        // Will return false at the end
    }

    return false;
}

等待任何反馈:)