SemVersion.java

SemVersion.java

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class SemVersion implements java.io.Serializable {

    private static final long serialVersionUID = 1L;
    private final static SemVersion UNKNOWN_VERSION = new SemVersion(0, 0, 0, null);
    private static final Pattern SEMVER_PATTERN = Pattern.compile("(\\d)\\.(\\d)\\.(\\d)([A-Za-z0-9\\.\\+-]*)?$");

    private final int majorVersion;
    private final int minorVersion;
    private final int patchLevel;
    private final String snapshotInfo;

    public static SemVersion parse(String versionStr) {
        Matcher m = SEMVER_PATTERN.matcher(versionStr);
        if (!m.matches())
            throw new IllegalArgumentException("unknown version format");
        return new SemVersion(versionInt(m, 1), versionInt(m, 2), versionInt(m, 3), snapshotInfo(m));
    }

    private static String snapshotInfo(Matcher matcher) {
        String _snapshotInfo = matcher.group(4);
        return _snapshotInfo.isEmpty() ? null : _snapshotInfo;
    }

    private static int versionInt(Matcher matcher, int pos) {
        return Integer.parseInt(matcher.group(pos));
    }

    protected SemVersion(int major, int minor, int patch, String snapshot) {
        this.majorVersion = major;
        this.minorVersion = minor;
        this.patchLevel = patch;
        this.snapshotInfo = snapshot;
    }

    public static SemVersion unknownVersion() {
        return UNKNOWN_VERSION;
    }

    public boolean isUknownVersion() {
        return (this == UNKNOWN_VERSION);
    }

    public boolean isSnapshotInfo() {
        return (snapshotInfo != null && snapshotInfo.length() > 0);
    }

    public boolean isSnapshot() {
        return isSnapshotInfo() && snapshotInfo.endsWith("SNAPSHOT");
    }

    public int getMajorVersion() {
        return majorVersion;
    }

    public int getMinorVersion() {
        return minorVersion;
    }

    public int getPatchLevel() {
        return patchLevel;
    }

    public String getSnapshotInfo() {
        return snapshotInfo;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append(majorVersion).append('.');
        sb.append(minorVersion).append('.');
        sb.append(patchLevel);
        if (snapshotInfo != null) {
            sb.append(snapshotInfo);
        }
        return sb.toString();
    }

    @Override
    public int hashCode() {
        return majorVersion ^ minorVersion + patchLevel;
    }

    @Override
    public boolean equals(Object o) {
        if (o == this)
            return true;
        if (o == null)
            return false;
        if (o.getClass() != getClass())
            return false;

        SemVersion other = (SemVersion) o;
        return (other.majorVersion == majorVersion) && (other.minorVersion == minorVersion)
                && (other.patchLevel == patchLevel)
                && (other.snapshotInfo == null ? snapshotInfo == null : other.snapshotInfo.equals(snapshotInfo));
    }
}

VersionTest.java

package org.polyglotted.attribrepo.core;

import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;

import org.junit.Test;

public class VersionTest {

    @Test(expected = IllegalArgumentException.class)
    public void testUnknownFormat() {
        assertNull(SemVersion.parse("1.2-rc1"));
    }

    @Test
    public void testPattern() {
        assertNotNull(SemVersion.parse("1.2.0"));
        assertNotNull(SemVersion.parse("1.2.0-SNAPSHOT"));
        assertNotNull(SemVersion.parse("1.2.0-alpha-a.b-c+build.1-ref.1-its-okay"));
    }
}