Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Core Source Code files are provided in the source packge (jackson-core-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Core Source Code below:

⏎ com/fasterxml/jackson/core/Version.java

/* Jackson JSON-processor.
 *
 * Copyright (c) 2007- Tatu Saloranta, tatu.saloranta@iki.fi
 */

package com.fasterxml.jackson.core;

/**
 * Object that encapsulates versioning information of a component.
 * Version information includes not just version number but also
 * optionally group and artifact ids of the component being versioned.
 *<p>
 * Note that optional group and artifact id properties are new with Jackson 2.0:
 * if provided, they should align with Maven artifact information.
 */
public class Version
    implements Comparable<Version>, java.io.Serializable
{
    private static final long serialVersionUID = 1L;

    private final static Version UNKNOWN_VERSION = new Version(0, 0, 0, null, null, null);

    protected final int _majorVersion;

    protected final int _minorVersion;

    protected final int _patchLevel;

    protected final String _groupId;

    protected final String _artifactId;

    /**
     * Additional information for snapshot versions; null for non-snapshot
     * (release) versions.
     */
    protected final String _snapshotInfo;

    /**
     * @param major Major version number
     * @param minor Minor version number
     * @param patchLevel patch level of version
     * @param snapshotInfo Optional additional string qualifier
     *
     * @since 2.1
     * @deprecated Use variant that takes group and artifact ids
     */
    @Deprecated
    public Version(int major, int minor, int patchLevel, String snapshotInfo)
    {
        this(major, minor, patchLevel, snapshotInfo, null, null);
    }

    public Version(int major, int minor, int patchLevel, String snapshotInfo,
            String groupId, String artifactId)
    {
        _majorVersion = major;
        _minorVersion = minor;
        _patchLevel = patchLevel;
        _snapshotInfo = snapshotInfo;
        _groupId = (groupId == null) ? "" : groupId;
        _artifactId = (artifactId == null) ? "" : artifactId;
    }

    /**
     * Method returns canonical "not known" version, which is used as version
     * in cases where actual version information is not known (instead of null).
     *
     * @return Version instance to use as a placeholder when actual version is not known
     *   (or not relevant)
     */
    public static Version unknownVersion() { return UNKNOWN_VERSION; }

    /**
     * @return {@code True} if this instance is the one returned by
     *    call to {@link #unknownVersion()}
     *
     * @since 2.7 to replace misspelled {@link #isUknownVersion()}
     */
    public boolean isUnknownVersion() { return (this == UNKNOWN_VERSION); }

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

    /**
     * @return {@code True} if this instance is the one returned by
     *    call to {@link #unknownVersion()}
     *
     * @deprecated Since 2.7 use correctly spelled method {@link #isUnknownVersion()}
     */
    @Deprecated
    public boolean isUknownVersion() { return isUnknownVersion(); }

    public int getMajorVersion() { return _majorVersion; }
    public int getMinorVersion() { return _minorVersion; }
    public int getPatchLevel() { return _patchLevel; }

    public String getGroupId() { return _groupId; }
    public String getArtifactId() { return _artifactId; }

    public String toFullString() {
        return _groupId + '/' + _artifactId + '/' + toString();
    }

    @Override public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append(_majorVersion).append('.');
        sb.append(_minorVersion).append('.');
        sb.append(_patchLevel);
        if (isSnapshot()) {
            sb.append('-').append(_snapshotInfo);
        }
        return sb.toString();
    }

    @Override public int hashCode() {
        return _artifactId.hashCode() ^ _groupId.hashCode() + _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;
        Version other = (Version) o;
        return (other._majorVersion == _majorVersion)
            && (other._minorVersion == _minorVersion)
            && (other._patchLevel == _patchLevel)
            && other._artifactId.equals(_artifactId)
            && other._groupId.equals(_groupId)
            ;
    }

    @Override
    public int compareTo(Version other)
    {
        if (other == this) return 0;
        
        int diff = _groupId.compareTo(other._groupId);
        if (diff == 0) {
            diff = _artifactId.compareTo(other._artifactId);
            if (diff == 0) {
                diff = _majorVersion - other._majorVersion;
                if (diff == 0) {
                    diff = _minorVersion - other._minorVersion;
                    if (diff == 0) {
                        diff = _patchLevel - other._patchLevel;
                    }
                }
            }
        }
        return diff;
    }
}

⏎ com/fasterxml/jackson/core/Version.java

Or download all of them as a single archive file:

File name: jackson-core-2.14.0-sources.jar
File size: 497693 bytes
Release date: 2022-11-05
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