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<title>new-instance</title>
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<h1>new-instance</h1>

<h2>Purpose</h2>

<p>
Construct a new instance of the indicated type, storing a reference to it in the
destination. The type must refer to a non-array class. 
</p>

<h2>Details</h2>

<table class="instruc">
<thead>
<tr>
  <th>Op &amp; Format</th>
  <th>Mnemonic / Syntax</th>
  <th>Arguments</th>
</tr>
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<tbody>
<tr>
  <td>22 21c</td>
  <td>new-instance vAA, type@BBBB</td>
  <td><code>A:</code> destination register (8 bits)<br/>
    <code>B:</code> type index</td>
</tr>
</tbody>
</table>

<h2>Constraints</h2>

<ul>
  <li>
    A must be a valid register index for the current stack frame.
  </li>
  <li>
    B must be a valid index into the type pool.
  </li>
  <li>
    Type constant pool entry B must contain a valid type descriptor for a
    non-array class.
  </li>
</ul>

<h2>Behavior</h2>

<ul>
  <li>
    An attempt is made to get a reference to the class C the name of which is
    contained in type pool entry B.
  </li>
  <li>
    If C has not been loaded and resolved before, it is being loaded and
    resolved. All exceptions that are possible during class loading can occur at
    this point.
  </li>
  <li>
    An attempt is made to create a new instance I of C. All exceptions that are
    possible during instantiation can occur at this point.
  </li>
  <li>
    A reference to the new instance is stored in register vA, that is vA' = I.
  </li>
  <li>
    If v(A-1) is the lower part of a register pair, v(A-1)' becomes undefined.
  </li>
  <li>
    If v(A+1) is the upper part of a register pair, v(A+1)' becomes undefined.
  </li>     
</ul>

<h2>Exceptions</h2>

<ul>
  <li>
    All exceptions that are possible during class loading can occur.
  </li>
  <li>
    All exceptions that are possible during instantiation can occur.
  </li> 
</ul>

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