Question

我有以下代码，负责为用户分配角色和组。

private void override(List<Assignment> assignments) {
    removeAll();
    addMultiple(assignments);
}

protected void removeAll() {
    removeAllRoles();
    removeAllGroups();
}

private void removeAllGroups() {
    Iterator<String> userGroups = user.getParentGroups(false);
    while (userGroups.hasNext()) {
        UMHelper.removeUserFromGroup(user.getUniqueID(), userGroups.next());
    }
}

private void addMultiple(List<Assignment> assignments) {
    for (Assignment assignment : assignments) {
        add(assignment);
    }
}

public static void addUserToGroup(String userId, String groupId) {
    try {
            SimpleLogger.log(Severity.INFO, Category.APPLICATIONS, loc, null, "Trying to add user " + userId + " to group " + groupId);
            groupFactory.addUserToGroup(userId, groupId);
            SimpleLogger.log(Severity.INFO, Category.APPLICATIONS, loc, null, "Success");
        } catch (UMException e) {
            SimpleLogger.traceThrowable(Severity.ERROR, loc, "Addition failed", e);
        }
}

我希望逻辑非常明确。大多数代码都是对集合进行迭代。将用户添加到角色或组可能会导致异常，我在日志中报告。

由于我发现抑制异常并不好，因为调用override方法的客户端应该知道分配的结果，所以我重写了添加异常处理的代码。 执行应该继续，即使某些分配失败。

private void override(List<Assignment> assignments) {
    SimpleLogger.log(Severity.INFO, Category.APPLICATIONS, loc, null, "Override was started with " + assignments.size() + " assignments");

    try {
        removeAll();
    } catch (UMException e) {
        SimpleLogger.log(Severity.INFO, Category.APPLICATIONS, loc, null, "Removing all existing elements failed");
    }

    try {
        addMultiple(assignments);
    } catch (UMException e) {
        SimpleLogger.log(Severity.INFO, Category.APPLICATIONS, loc, null, "Adding new elements failed");
    }
}

protected void removeAll() throws UMException {
    boolean successfulRemoval = true;

    try {
        removeAllRoles();
    } catch (UMException e) {
        successfulRemoval = false;
    }

    try {
        removeAllGroups();
    } catch (UMException e) {
        successfulRemoval = false;
    }

    if (!successfulRemoval){
        throw new UMException("Not all user elements could be removed");
    }
}

private void removeAllGroups() throws UMException {
    boolean removeSuccessful = true;

    Iterator<String> userGroups = user.getParentGroups(false);
    while (userGroups.hasNext()) {
        try {
            UMHelper.removeUserFromGroup(user.getUniqueID(), userGroups.next());
        } catch (UMException e) {
            removeSuccessful = false;
        }
    }

    if (!removeSuccessful) {
        throw new UMException("Not all user groups could be removed");
    }
}

private void addMultiple(List<Assignment> assignments) throws UMException {
    boolean additionSuccessful = true;

    for (Assignment assignment : assignments) {
        try {
            add(assignment);
        } catch (UMException e) {
            additionSuccessful = false;
        }
    }

    if (!additionSuccessful) {
        throw new UMException("Addition of new rights failed");
    }
}

public static void addUserToGroup(String userId, String groupId) throws UMException {
        SimpleLogger.log(Severity.INFO, Category.APPLICATIONS, loc, null, "Trying to add user " + userId + " to group " + groupId);
        groupFactory.addUserToGroup(userId, groupId);
        SimpleLogger.log(Severity.INFO, Category.APPLICATIONS, loc, null, "Success");
}

现在代码增加了3倍，并没有像现在这样清晰。如果我只是在第一次分配失败后不得不停止执行，代码会更容易，但这是要求。我是否处理了异常错误或有没有办法改进代码？

Answer 1

在这种情况下，我会将所有这些方法从抛出异常改为
返回一个布尔值，表示他们是否成功完成了工作如果您可以控制这些方法并且可以进行此更改，我认为这更好适合您的场景。

Answer 2

通过一些代码重组，即所有删除/添加/等都在一个事务中，代码可以更清晰，例如：

String failmsg = null;

// tx is some transaction object
tx.start();
try {
    failmsg = "user removal failed";
    tx.removeUsers();
    failmsg = "group removal failed";
    tx.removeGroups();
    failmsg = "new additions failed";
    tx.addNew();
    tx.commit();
} catch (UMException e) {
    tx.rollback();
    log(failmsg);
} finally {
    tx.close();
}

异常处理使代码逻辑不清楚

2 个答案: