Remove comma at the start of String Array in Java
<p>I have multiple String[], some of them start with a comma. How i can remove this comma in a loop on all of the Arrays.</p>

<p>result:</p>

<pre><code>[,a,b,c,d]
[e,f,g,h,i]
[,j,k,l,m,n]
[w,x,y,z]
</code></pre>

<p>Code:</p>

<pre><code>        HashMap&lt;String, String[]&gt; newHashMap = new HashMap();
        String[] baseVectorArray;
        for (String name : externalMap.keySet()) {
            if (!name.isEmpty()) {
                StringBuilder bv = new StringBuilder();
                HashMap&lt;String, List&lt;String&gt;&gt; l = oldHashMap.get(name);
                List&lt;String&gt; list_of_names;
                for (String id : l.keySet()) {
                    list_of_authors = l.get(id);
                    for (String s : list_of_names) {
                        bv.append(s);
                        bv.append(", ");
                    }
                }
                bv.deleteCharAt(bv.lastIndexOf(","));
                String bvs = bv.toString();
                String[] bva = bvs.split(",");

                System.out.println(Arrays.toString(bva));
                newHashMap.put(name, bva);
            }
        }
</code></pre>