Null value dereference [LUCENE-6602]

[asfimport]

In the file BoostQueryNode.java, getChild could be null and it is being dereferenced in the function toString().

  public QueryNode getChild() {
    List<QueryNode> children = getChildren();

    if (children == null || children.size() == 0) {
      return null;
    }

    return children.get(0);

  }

public String toString() {
    return "<boost value='" + getValueString() + "'>" + "\n"
        + getChild().toString() + "\n</boost>";
  }

Should we not check if getChild is valid?

String s = (getChild() != null) ? getChild().toString() : "null";
return "<boost value='" + getValueString() + "'>" + "\n"
        + s + "\n</boost>";

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Migrated from LUCENE-6602 by Rishabh Patel, updated May 09 2016

[asfimport]

ASF GitHub Bot (migrated from JIRA)

GitHub user rmp91 opened a pull request:

https://github.com/apache/lucene-solr/pull/159

LUCENE-6602: Checking for null getChild() before getChild.toString()

https://issues.apache.org/jira/browse/LUCENE-6602

You can merge this pull request into a Git repository by running:

$ git pull https://github.com/rmp91/lucene-solr LUCENE-6602

Alternatively you can review and apply these changes as the patch at:

https://github.com/apache/lucene-solr/pull/159.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

This closes `#159`

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commit 3b8874be7c365f68bfbec204ab7043b4fe6098ad
Author: Rishabh <rishabh.mahendra.patel@gmail.com>
Date: 2015-06-25T02:47:38Z

LUCENE-6602: Added a check for Null value, before executing getChild.toString()

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