The Java garbage collector (GC) reclaims objects that are not traceable starting from a set of GC roots. That is, if object A is referenced by object B, and object B is referenced by object C, and object C is referenced by a root, then objects A, B, and C are all safe from the … Read more
Try this: JSONArray array; for(int i = 0; i < array.length(); i++){ JSONObject json = array.getJSONObject(i); if (json.has(“errors”)){ //magic } } solved JSONArray equivalent to JSONObject’s .has() method?
I think you almost answer your own question. Create a class-hierarchy with the “Animal”-interface as the top-node. I made an example of the hierarchy here. Also, inheritance and polymorphi is some of the essentials of OOP, so I don’t get your last sentence. solved about OOP and inherited classes
For PUT use RestTemplate.exchange() method Example MyJaxbRequestDataObjectrequest = createMyJaxbRequestDataObject(); Map<String, String> uriArguments= createUriArguments(); String url = restBaseUrl + “/myputservice/{usertId}?servicekey={servicekey}”; HttpHeaders headers = new HttpHeaders(); headers.setContentType(MediaType.APPLICATION_XML); HttpEntity<MyJaxbRequestDataObject> entity = new HttpEntity<MyJaxbRequestDataObject>(request, headers); ResponseEntity<MyJaxbResponseDataObject> responseWrapper = shogunRestTemplate.exchange(url, HttpMethod.PUT, entity, MyJaxbResponseDataObject.class, uriArguments); MyJaxbResponseDataObjectresponse = responseWrapper.getBody(); solved How can I make a Put rest call along with POJO using … Read more
A few things on readability: First codeblock: I would have the counters counting in the same direction– it will still compare each word this way. It’s not a terribly important change, but it can save the reader a step so that they don’t have to do any mental math to determine if the code is … Read more
Just write your if loop after declaration of your all the views in your onCreate() as below: @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); buttonSend = (Button) findViewById(R.id.buttonSend); textTo = (EditText) findViewById(R.id.editTextSendTo); textSubject = (EditText) findViewById(R.id.editTextName); textMessageContact = (EditText) findViewById(R.id.editTextContact); textMessageEmail = (EditText) findViewById(R.id.editTextEmail); textMessageAmount = (EditText) findViewById(R.id.editTextAmount); spinner = (Spinner) findViewById(R.id.spinner); buttonSend.setOnClickListener(new OnClickListener() … Read more
This code works, I just ran it with a loop of 1000000. The easiest solution is probably to just create a new project and copy the code into that. solved ArrayIndexOutOfBoundsException but I can’t see where it goes out of bounds
Java programs (like all programs) require a CPU and memory to operate instructions. Both elements are complex electrical circuits, they cannot work without electricity. The only thing you can do to persist the state of your application, is to write information regarding that state to disc. The Google File System uses this method to ensure … Read more
A function works like this: The first line of code public int foo (int n, int f) is the function declaration with its visibility (public), its return data type (int), its name (foo) and its parameters (n of the type int and f of the type int). What the visibility is, is not important for … Read more
Please follow comments mentioned at every step public class Main { public static void main(String[] args) { int[] numbers = {1, 2, 3}; // create a new array of intergers as {1,2,3} int length = numbers[2]; // assign 3 to variable ‘length’ char[] chars = new char[length]; // create a char array of size 3 … Read more
static class Message { String message; long time; public Message(String message, long time) { this.message = message; this.time = time; } } public static void putLatestMessage(Map<String, Message> messageMap, Message message) { if (messageMap.containsKey(message.message) && messageMap.get(message.message).time >= message.time) { return; } else { messageMap.put(message.message, message); } } public static void main(String[] args) { Map<String, Message> messageMap … Read more
Why instance variables are not initialized before constructor creation. What happens if they are initialized at the class loading itself [closed] solved Why instance variables are not initialized before constructor creation. What happens if they are initialized at the class loading itself [closed]
To get the sum of the elements as your question states, you can use streams. int sum = history.stream() .filter(his->his.getRes().equals(“Vundet”)) .mapToInt(his->his.getWins()) // assuming this getter exists. .sum(); 2 solved Get the sum of elements of an ArrayList
Another option is to parse the XML, and use the OutputKeys.INDENT option of the Transformer class to output the XML formatted. The following example Source source = new StreamSource(new StringReader(s)); TransformerFactory transformerFactory = TransformerFactory.newInstance(); transformerFactory.setAttribute(“indent-number”, 4); Transformer transformer = transformerFactory.newTransformer(); transformer.setOutputProperty(OutputKeys.INDENT, “yes”); StreamResult result = new StreamResult(new StringWriter()); transformer.transform(source, result); String xmlOutput = result.getWriter().toString(); System.out.println(xmlOutput); … Read more
instead of nowh.before(enh) && nowh.after(sth) use nowh.before(enh) && nowh.after(sth) && sth.before(enh) || enh.before(sth) && !(nowh.before(enh) && nowh.after(sth)) Apart from that I think Calendar class is supposed to be used differently I assume… solved How can I compare two hours in java?