title: What is the meaning of "&" in java
body: <p>I have this code</p>
  
  <pre><code>  import java.io.*; import java.util.*;
  import javax.xml.parsers.*; import org.xml.sax.InputSource;
  class TeamPlayer {
      private int pulse;
      TeamPlayer() { pulse= -10; }
      TeamPlayer(int v0) {pulse= v0 +5;}
      public int m(int v) { return 31%3 ;}
      public int get_pulse() { return 1* pulse;}
  }
  class GoalKeeper extends TeamPlayer {
      GoalKeeper() { stress -=8; }
      public static int stress=3;
      public int m(int v) { return (v &amp; 3) + 15; }
  }
  </code></pre>
  
  <p>but I can't understand what "&amp;" means. Is it different from "&amp;&amp;"?</p>