java - 如何处理调用 null 返回方法的方法中的 null 值？

Question

这是示例代码

public OperationResult beforeEverything(BDDObject savingObject) {

  String checkAssetRole = doCheckAssetRole(savingObject);

  if (checkAssetRole != null && !checkAssetRole.equals("MissingAssetRole")) {
    return new OperationResult(new OperationExecutionError("SIP-37006",
                               new String[] {"Duplicate asset roles have been defined: " + checkAssetRole},
                               getLocalizationGate()));
  }
  ArrayList<String> warnings = new ArrayList<String>();
  boolean showWarning = false;

  if (checkAssetRole != null && checkAssetRole.equals("MissingAssetRole")) {
    mLogger.debug("Warning  of Asset role");
    warnings.add(new String(
                "Asset role is missing. Do you want to save the record?"));
    showWarning = true;
  }
  return OperationResult.OK;
}

问题是 doCheckAssetRole 方法返回 null。那么我该如何在 beforeEverything() 方法中处理它呢？是否需要进行一些异常处理？如果是这样，怎么办？

Answer 1

进行 null 检查，然后使用 message 抛出 RuntimeException 。

 if(checkAssetRole==null)
      throw new RuntimeException ("AssetRole value is NULL.");

你的代码看起来像这样。

String checkAssetRole = doCheckAssetRole(savingObject);

if(checkAssetRole==null)
      throw new RuntimeException ("AssetRole value is NULL.");

if (checkAssetRole != null && !checkAssetRole.equals("MissingAssetRole")) {
return new OperationResult(new OperationExecutionError("SIP-37006",
                           new String[] {"Duplicate asset roles have been defined: " + checkAssetRole},
                           getLocalizationGate()));
}