Question

I’m trying to build an application in Android using some codes from Objective-C (IPhone app).I’m trying to understand what exactly is doing a piece of code and translate it into Java code,but I think I need a little help here.So first, here is the Obj-C code :

  (BOOL)processSqlInjectQueries:(NSArray *)injectQueries error:(NSError**)error {
    //some code

    for(NSDictionary * q in injectQueries)
                {
                    if (![q isKindOfClass:[NSDictionary class]]) continue;

                    StPacketInjectQueryPackage qType  = (StPacketInjectQueryPackage)[[q objectForKey:@"type"] intValue];
                    NSString * query = [q objectForKey:@"query"];
                }
    //some code
    }

In Java, I’m trying to do something like this :

         // in some other method :

        JSONObject jsonData= new JSONObject();
        String authHash = jsonData.getJSONObject("client_auth_hash").toString();
        List<Map<String,String>> injectQueries= new ArrayList<Map<String,String>>();
        injectQueries.add(new HashMap<String, String>());
        //injectQueries.add(authHash);


    public boolean processSqlInjectQueries(List<Map<String,String>> injectQueries, Exception error){

        if(injectQueries==null || injectQueries.size()==0){
            boolean injectsProcessed = this.processSqlInjectQueries(injectQueries,error);
            if(!injectsProcessed){
                return false;
            }
        }

        Log.i("Info","Processing INJECT Queries...");
        boolean res = true;
        /*[_dbAdapter beginTransaction];
        [_user.userDbAdapter beginTransaction];*/

        for(Map<String,String> b : injectQueries){

            if(b.getClass().getName()!=injectQueries.getClass().getName()){
                continue;
            }
            //RPCPacketInjectQueryPackage qType = (RPCPacketInjectQueryPackage) 
        }

        return true;
    }

But my problem is that is that I get this error : Type mismatch: cannot convert from element type Object to ArrayList.

Any suggestion how to fix that error?

And second question : Can I use Exception error in declaraion of processSqlInjectQueries instead of NSError *error in Obj-C?

Answer 1

The objective C code is passing through an NSArray containing NSDictionaries through to the method, so the following is probably closer to what you want to do…

public boolean processSqlInjectQueries(List<Map<String,String> injectQueries) {
    for(Map<String,String> q : injectQueries) {
        // do stuff with q
    }
}

To handle the error code, you probably want to think about throwing an exception rather than trying to pass through an “Error” object, so something like the following:

public boolean processSqlInjectQueries(List<Map<String,String> injectQueries) throws Exception {
    for(Map<String,String> q : injectQueries) {
        // do stuff with q
    }

    if(errorConditionOccurs) {
       throw new Exception();
    }
}

You’ll want to tailor the exact Exception that’s thrown so it matches whatever your code is trying to do.

In response to comment: perhaps this is closer to what you’re trying to do?

public boolean processSqlInjectQueries(JSONObject jsonObject) {
    for(String key : jsonObject.keys()) {
        Object value = jsonOnject.get(key);
        // Do stuff with value
    }
    // Do more stuff
}

And you could call it with:

processSqlInjectQueries(jsonData.getJSONObject("client_auth_hash"));