If you mean, which is better for readability, this: if (condition) { // do something return true; } // do something else return false; Or this: if (condition) { // do something return true; } else { // do something else return false; } Definitely the first one is better for readability. Logically, they’re equivalent. … Read more
on my second class called next class, last line of public array list search for price the .indexOf double cant be dereferenced? solved on my second class called next class, last line of public array list search for price the .indexOf double cant be dereferenced?
The first constructor U() calls the second constructor U(int x) via the this(2) call. The second constructor U(int x) calls the super class constructor T() implicitly. Which means both U constructors call the super class constructor, either directly or indirectly. solved Super constructor call order [duplicate]
SQLiteException: no such column: _idmoneyreasonDAte: […] while compiling: SELECT _idmoneyreasonDAte FROM MONEY_TABLE You are selecting all values of a column (called _idmoneyreasonDAte) that doesn’t exist in the table MONEY_TABLE. The bug is here: public String getData() { // TODO Auto-generated method stub String[] columns= new String[]{ KEY_ID + KEY_MONEY + KEY_REASON + KEY_DATE }; Cursor … Read more
Q: What (if any) argument gets passed in to studentList.addStudent()? A: That depends entirely on what parameters the addStudent() method of “studentList’s` class takes. In your case: studentList is a Manager (poor name for either variable or class, but..) Manager.addStudent() takes an object of class type Student. You need to have an object of type … Read more
The switch statement jumps to the case that matches, and continues processing from there until it sees a break. Since there are no breaks in that code, it starts at case 1, outputs 1, and then continues with case 2 and outputs 2. Although it’s rare, sometimes this “fall through to the next case” is … Read more
Assuming your ArrayList is this: List<String[]> arrayList = new ArrayList<>(); arrayList.add(new String[]{“R111″,”Red”,”50000″}); arrayList.add(new String[]{“R123″,”Blue”,”50000″}); you can do something like: for (Iterator<String[]> iterator = arrayList.iterator();iterator.hasNext();) { String[] stringArray = iterator.next(); if(“R111”.equals(stringArray[0])) { iterator.remove(); } } You can safely remove an element using iterator.remove() while iterating the ArrayList. Also see The collection Interface. An alternative shorter approach … Read more
You can create a recursive function, public void loopThrough(List<Region> regions) { for(Region region : regions) { if(region.hasSubRegion()) { loopThrough(region.getSubRegions()); } } } 1 solved Iterate through a possibly infinite amount of nested ArrayLists
Try this: public class Test { public static void main(String[] args) { String[] saveSpace = { “abcd: 1234”, “abcd : 1234”, “abcd : abcd dgdfgdf abcd dgdsfsdf”, “abcd 1234”, “asdasdas abcd abcd: sdfdsf” }; String regex = “abcd(?!\\s*\\w)(?=(?:[^:]*\\:){1}[^:]*$)”; String replace = “xyz”; for(int i = 0; i<saveSpace.length; i++) { saveSpace[i] = saveSpace[i].replaceFirst(regex, replace); System.out.println(saveSpace[i]); } … Read more
So here is your code in Java: public class MainActivity extends AppCompatActivity implements View.OnClickListener { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); findViewById(R.id.increase).setOnClickListener(this) findViewById(R.id.decrease).setOnClickListener(this) } public void increaseInteger() { display(Integer.parseInt(integer_number.getText().toString()) + 1); } public void decreaseInteger() { display(Integer.parseInt(integer_number.getText().toString()) – 1); } private fun display(int number) { integer_number.setText(String.valueOf(number)); } @Override protected void onClick(View v) { … Read more
You should change Collections.sort(array, new j()); to Arrays.sort(array, new j()); solved Java error :- “no suitable method found for sort(Student[],j)”
The lenght of the array is limited to the arguments used. So if you have 3 arguments (java Program 1st 2nd 3rd) then you will not be able to access more than that (e.g. args[3] for the 4th) To assign a new value to an existing argument is possible. But I have no idea for … Read more
Oh my god, thanks @Orel Eraki, of course beside the unbalanced single-quotes you will have to follow proper SQL Insert Syntax and hava a form of ‘INSERT INTO …’, try it like this (see my change dirctly after “values(” as the one of Orel Eraki (no ‘table’ “keyword” after into): Sql_insert=”insert into itemmanag(itemID,purchesPrice,sellPrice,quantity,vendor,unitM )values(‘”+txt_itemID.getText()+”‘,'”+Item_Pprice.getText()+”‘,'”+txt_itemSprice.getText()+”‘,'”+txt_qunti.getText()+”‘,'” +jcombo1+”‘,'”+jcombo2+ … Read more
Swap the arguments to the phonebook constructor public static void main(String[] args) { Scanner input = new Scanner(System.in); String area, inStr; //there is no need of inStr as you are not using it so remove it if not used int pages; System.out.println(“Please enter your city”); area = input.nextLine(); System.out.println(“Please enter page number ” + area … Read more
No. A class with an incomplete implementation must be declared abstract. It cannot be directly instantiated, but it can serve as a common base for subclasses to build upon. The point of all this is that the compiler can make sure that when a method is called on an object (as defined by the interface), … Read more