PageResource(int pageBudget, Space space, Address start) { this(pageBudget, space); this.start = start; this.contiguous = true;
PageResource(int pageBudget, Space space) { this.pageBudget = pageBudget; gcLock = new Lock(space.getName() + ".gcLock"); mutatorLock = new Lock(space.getName() + ".mutatorLock");
  PageResource(int pageBudget, Space space, Address start) {    this(pageBudget, space);    this.start = start;    this.contiguous = true;  }