mybatis-plus/mybatis-plus-extension/src/main/java/com/baomidou/mybatisplus/extension/toolkit/VersionUtils.java

package com.baomidou.mybatisplus.extension.toolkit;

import com.baomidou.mybatisplus.core.exceptions.MybatisPlusException;
import com.baomidou.mybatisplus.core.toolkit.StringUtils;

/**
 * <p>
 * VersionUtils ，比较版本号
 * </p>
 *
 * @author Caratacus
 * @Date 2016-12-5
 */
public class VersionUtils {

    /**
     * 比较版本号的大小,前者大则返回一个正数,后者大返回一个负数,相等则返回0
     *
     * @param version1
     * @param version2
     * @return
     */
    public static int compareVersion(String version1, String version2) {
        if (StringUtils.isEmpty(version1) || StringUtils.isEmpty(version2)) {
            throw new MybatisPlusException("Error: CompareVersion Error: Illegal Argument !" );
        }
        // 切割点 "."；
        String[] versionArray1 = version1.split("\\." );
        String[] versionArray2 = version2.split("\\." );
        int idx = 0;
        // 取最小长度值
        int minLength = Math.min(versionArray1.length, versionArray2.length);
        int diff = 0;
        // 先比较长度 再比较字符
        while (idx < minLength && (diff = versionArray1[idx].length() - versionArray2[idx].length()) == 0
            && (diff = versionArray1[idx].compareTo(versionArray2[idx])) == 0) {
            ++idx;
        }
        // 如果已经分出大小，则直接返回，如果未分出大小，则再比较位数，有子版本的为大；
        diff = (diff != 0) ? diff : versionArray1.length - versionArray2.length;
        return diff;
    }

    /**
     * 比较版本号 true
     *
     * @param version1
     * @param version2
     * @return boolean true v1>=v2 false相反
     */
    public static boolean compare(String version1, String version2) {
        int num = compareVersion(version1, version2);
        return num >= 0;
    }
}