我怎样才能重构这个switch语句？

function handleActions(action) {
  const actionsMap = {
    'CASE1': () => { /* do something */ },
    'CASE2': () => { /* do something else */ },
    // ...
  };

  if (actionsMap.hasOwnProperty(action)) {
    actionsMap[action]();
  } else {
    // handle default case
  }
}

function handleCase1() {
  // do something
}

function handleCase2() {
  // do something else
}

function handleActions(action) {
  switch (action) {
    case 'CASE1':
      handleCase1();
      break;
    case 'CASE2':
      handleCase2();
      break;
    // ...
  }
}

class Strategy {
  execute() {
    throw new Error('Not implemented');
  }
}

class Strategy1 extends Strategy {
  execute() {
    // do something
  }
}

class Strategy2 extends Strategy {
  execute() {
    // do something else
  }
}

function handleActions(action) {
  let strategy;

  switch (action) {
    case 'CASE1':
      strategy = new Strategy1();
      break;
    case 'CASE2':
      strategy = new Strategy2();
      break;
    // ...
  }

  strategy.execute();
}

function handleActions(action) {
  if (action === 'CASE1') {
    // do something
  } else if (action === 'CASE2') {
    // do something else
  } else {
    // handle default case
  }
}