code: public void setRelationships(java.util.Collection<Relationship> relationships) {
          if (relationships == null) {
              this.relationships = null;
              return;
          }
  
          this.relationships = new java.util.ArrayList<Relationship>(relationships);
      }
docs: <p>
  A list of child blocks of the current block. For example a LINE object has child blocks for each WORD block
  that's part of the line of text. There aren't Relationship objects in the list for relationships that don't
  exist, such as when the current block has no child blocks. The list size can be the following:
  </p>
  <ul>
  <li>
  <p>
  0 - The block has no child blocks.
  </p>
  </li>
  <li>
  <p>
  1 - The block has child blocks.
  </p>
  </li>
  </ul>
  
  @param relationships
  A list of child blocks of the current block. For example a LINE object has child blocks for each WORD
  block that's part of the line of text. There aren't Relationship objects in the list for relationships
  that don't exist, such as when the current block has no child blocks. The list size can be the
  following:</p>
  <ul>
  <li>
  <p>
  0 - The block has no child blocks.
  </p>
  </li>
  <li>
  <p>
  1 - The block has child blocks.
  </p>
  </li>