private boolean newerFirst = true;

    public MetadataGraphEdge apply(MetadataGraphEdge e1, MetadataGraphEdge e2) {
        int depth1 = e1.getDepth();
        int depth2 = e2.getDepth();

        if (depth1 == depth2) {
            ArtifactVersion v1 = new DefaultArtifactVersion(e1.getVersion());
            ArtifactVersion v2 = new DefaultArtifactVersion(e2.getVersion());

        return scope;
    }

    public void setScope(ArtifactScopeEnum scope) {
        this.scope = scope;
    }

    public int getDepth() {
        return depth;
    }

    public void setDepth(int depth) {
        this.depth = depth;
    }

    public boolean isResolved() {
        return resolved;
    }

    public void setResolved(boolean resolved) {
        this.resolved = resolved;

     */
    @Override
    public Integer getDepth() {
        return depth;
    }

    /*
     * (non-Javadoc)
     *
     * @see org.codelibs.fess.crawler.entity.UrlQueue#setDepth(java.lang.Integer)
     */
    @Override
    public void setDepth(final Integer depth) {
        this.depth = depth;
    }

    /*
     * (non-Javadoc)
     *

        }
        if (url != null) {
            builder.field(URL, url);
        }
        if (parentUrl != null) {
            builder.field(PARENT_URL, parentUrl);
        }
        if (depth != null) {
            builder.field(DEPTH, depth);
        }
        if (lastModified != null) {
            builder.field(LAST_MODIFIED, lastModified);
        }
        if (createTime != null) {

        this.remoteRepositories = remoteRepositories;
        depth = 0;
        parents = Collections.emptyList();
        parent = null;
    }

    public ResolutionNode(Artifact artifact, List<ArtifactRepository> remoteRepositories, ResolutionNode parent) {
        this.artifact = artifact;
        this.remoteRepositories = remoteRepositories;
        depth = parent.depth + 1;
        parents = new ArrayList<>();

      "nested2": { "nested2arr": [0,1,2], "nested3": {
        "nested4": { "depth": "recursion" }}
			}
		}
  },
  "2": {
    "nullfield": null,
    "id": -2
  }
}`
	)

	decoder := NewDecoder(mkReader(body), 2)

	for mv = range decoder.Stream() {
		counter++
		t.Logf("depth=%d offset=%d len=%d (%v)", mv.Depth, mv.Offset, mv.Length, mv.Value)
	}

	if err := decoder.Err(); err != nil {

			Length:    int(d.pos - offset),
			Depth:     d.depth,
			Value:     i,
			ValueType: t,
		}
	}
	return i, err
}

// return whether, at the current depth, the value being decoded will
// be emitted to stream
func (d *Decoder) willEmit() bool {
	if d.emitRecursive {
		return d.depth >= d.emitDepth
	}
	return d.depth == d.emitDepth
}

`jstream` is a streaming JSON parser and value extraction library for Go.

Unlike most JSON parsers, `jstream` is document position- and depth-aware -- this enables the extraction of values at a specified depth, eliminating the overhead of allocating encompassing arrays or objects; e.g:

Using the below example document:

            crawlerContext.setNumOfThread(numOfThread);

            // depth
            final int depth = webConfig.getDepth() != null ? webConfig.getDepth() : -1;
            crawlerContext.setMaxDepth(depth);

            // max count
            final long maxCount = webConfig.getMaxAccessCount() != null ? webConfig.getMaxAccessCount() : maxAccessCount;

    protected ThreadLocal<String[]> sitemapsLocal = new ThreadLocal<>();

    /** The number of a thread */
    protected int numOfThread = 10;

    protected int maxThreadCheckCount = 20;

    /** a max depth for crawling. -1 is no depth check. */
    protected int maxDepth = -1;

    /** a max count to access urls. 0 is no limit to access it. */
    protected long maxAccessCount = 0;

    public String getSessionId() {