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public static int cmpVersion(String ver1,String ver2){
        String [] sarr1=ver1.split("\\.");
        String [] sarr2=ver2.split("\\.");
        for(int i=0;i<sarr1.length;i++){
            int val1=Integer.parseInt(sarr1[i]);
            int val2=0;
            if(sarr2.length>i){
                val2=Integer.parseInt(sarr2[i]);
            }
            if(val1!=val2 ){
                return ((val1-val2)>0) ? -1 : 1;
            }
        }
        return 0;
    }

public int compareVersions(String v1, String v2){
		String[] sp1 = v1.split("\\.");
		String[] sp2 = v2.split("\\.");
	    int min = sp1.length>sp2.length?sp2.length:sp2.length;
	    for(int i=0; i<min; i++){
	    	int n1 = Integer.parseInt(sp1[i]);
	    	int n2 = Integer.parseInt(sp2[i]);
	    	if(n1==n2)
	    		continue;
	    	else{
	    		return (n1-n2)>0?-1:1;
	    	}
	    }
	    if(sp1.length!=sp2.length)
	    	return sp1.length>sp2.length?-1:1;
	    else
	    	return 0;
	}

public int compareVersion(String v1, String v2){
String v1_ = v1.replaceAll("\\D", "");
String v2_ = v2.replaceAll("\\D", "");
if (v1_.isEmpty() && !v2_.isEmpty()) return 1;
else if ( !v1_.isEmpty() && v2_.isEmpty()) return -1;
else if ( v1_.isEmpty() && v2_.isEmpty()) return 0;	// invalid inputs
return Integer.parseInt(v1_)>Integer.parseInt(v2_) ? -1 : 1;
}

private static int compareVersion(String ver1, String ver2) {
		String[] str1 = ver1.split("\\.");
		String[] str2 = ver2.split("\\.");
		int loopCount = str1.length > str2.length ? str1.length : str2.length;
		if (!str1[0].isEmpty() && !str2[0].isEmpty()) {
			for (int i = 0; i < loopCount; i++) {
				int v1 = Integer.parseInt(str1[i]);
				int v2 = Integer.parseInt(str2[i]);
				if (v1 == v2)
					continue;
				else if (v1 > v2) {
					int v11 = Integer.parseInt(str1[i].substring(0, 1));
					int v21 = Integer.parseInt(str2[i].substring(0, 1));
					if (v11 >= v21)
						return -1;
					else
						return 1;
				} else if (v2 > v1) {
					int v11 = Integer.parseInt(str1[i].substring(0, 1));
					int v21 = Integer.parseInt(str2[i].substring(0, 1));
					if (v21 >= v11)
						return 1;
					else
						return -1;
				}
			}
		} else if (str1[0].isEmpty() && str2[0].isEmpty()) {
			return 0;
		} else if (str1[0].isEmpty())
			return 1;
		else if (str2[0].isEmpty())
			return -1;
		else
			return 0;
		return 0;
	}

You can remove all the dots except the first dot. This will result in a floating point number. We can directly do the fp comparison.

package zhang.juanyong.algorithms2;

import java.util.Queue;

import org.apache.commons.lang.StringUtils;

public class VersionComparator {
	public static int compareVersion(String v1, String v2) {
		Queue<Integer> q1 = new java.util.LinkedList<Integer>();
		Queue<Integer> q2 = new java.util.LinkedList<Integer>();
		loadVersion(q1, v1);
		loadVersion(q2, v2);

		int comp = 0;
		while (!q1.isEmpty()) {
			comp = q1.poll().compareTo(q2.poll());
			if (0 != comp) {
				return comp;
			}
		}

		return comp;
	}

	private static void loadVersion(Queue<Integer> q, String version) {
		String[] vNums = StringUtils.split(version, ".");
		for (String v : vNums) {
			q.add(Integer.valueOf(v));
		}
	}

	public static void main(String[] args) {
		String v1 = "10.3.4";
		String v2 = "10.3.41";
		System.out.println(String.format("compareVersion(%s, %s)=%s", v1, v2,
				compareVersion(v1, v2)));
	}

}

Many of these cases fall short for irregular inputs such as 10.0 < 10.0.1

Rather than cast to an integer, my example uses string comparison (character by character comparison like strcmp in c) to determine which number is larger.

import java.util.*;
public class Version {
	public static int which(String version1, String version2) {
		String[] versionParts1 = version1.split("\\.");
		String[] versionParts2 = version2.split("\\.");
		int maxLength = Math.max(versionParts1.length, versionParts2.length);
		int compare = 0;
		for(int i=0; i < maxLength && compare==0; i++) {
			// version 2 is an extended version of version1
			if(versionParts1.length==i) {
				compare=1; 
			// version 1 is an extended version of version2
			} else if(versionParts2.length==i) { 
				compare=-1; 
			} else {
				compare = versionParts2[i].compareTo(versionParts1[i]);
			}

		}
		return Integer.signum(compare); 
	}
	public static void main(String[] args) {
		System.out.println(which(args[0], args[1]));
	}
}

String v1=version1.replace(".","");
        String v2 =version2.replace(".","");
        if (Integer.parseInt(v1)==Integer.parseInt(v2)){
            System.out.println("0");
        }else
        System.out.println(Integer.parseInt(v1)>Integer.parseInt(v2)?"-1":"+1");

String v1=version1.replace(".","");
        String v2 =version2.replace(".","");
        if (Integer.parseInt(v1)==Integer.parseInt(v2)){
            System.out.println("0");
        }else
        System.out.println(Integer.parseInt(v1)>Integer.parseInt(v2)?"-1":"+1");

String v1=version1.replace(".","");
        String v2 =version2.replace(".","");
        if (Integer.parseInt(v1)==Integer.parseInt(v2)){
            System.out.println("0");
        }else
        System.out.println(Integer.parseInt(v1)>Integer.parseInt(v2)?"-1":"+1");