How to remove items from list in java?

How to remove items from list in java?

There are two remove() methods to remove elements from the List.

  1. E remove(int index): This method removes the element at the specified index and return it. The subsequent elements are shifted to the left by one place.
  2. boolean remove(Object o): This method removes the first occurrence of the specified object.

Does list Remove use equals?

ArrayList remove() relies on the objects implementation of the Equal method. If no implementation has been done then the object is removed by Object ‘s implementation of Equals which indeed is the pointer comparison.

How to remove all occurrences of a number from a list in java?

Remove all occurrences of an element from a List in Java

  1. Using List.removeAll() method. The List interface provides the removeAll() method that removes all elements in the list that are contained in the specified collection.
  2. Using List. removeIf() method.
  3. Using List. remove() method.

How to remove list of values from another list in java?

How to remove a SubList from a List in Java

  1. Method 1: Using subList() and clear() method. Syntax: List.subList(int fromIndex, int toIndex).clear() Example: // Java code to remove a subList using.
  2. Method 2: Using removeRange() method. Syntax: List.removeRange(int fromIndex, int toIndex) Example:

How do I remove objects from a list?

There are three ways in which you can Remove elements from List:

  1. Using the remove() method.
  2. Using the list object’s pop() method.
  3. Using the del operator.

How do I remove multiple elements from a list in Java?

2. Examples

  1. Remove multiple objects using List. removeAll method. If both are collection objects and we want to remove all element from another collection then removeAll can be used.
  2. Remove multiple objects using List. removeIf (Java 8)
  3. Remove multiple objects using Iterator (Java 7) Remove elements using Iterator.

How do I remove a value from a list?

How do I remove a specific string from a list in Java?

Remove an Element from ArrayList in Java

  1. Using ArrayList.remove() Method. By index. By element.
  2. Using Iterator.remove() Method.
  3. Using ArrayList.removeIf() Method.

How do you clear an object in Java?

You can delete an object in Java by removing the reference to it by assigning null. After that, it will be automatically deleted by the Garbage Collector. You just simply never worry about having to do that. All those recommendations, setting references to null, calling gc(), don’t do it.

How do you destroy an object in Java?

Java doesn’t let you destroy objects. Any unreachable object may (or may not) be GCed at any particular point in time….To clarify why the other answers can not work:

  1. System.
  2. Runtime.
  3. Object has no delete method.
  4. While Object does have a finalize method, it doesn’t destroy anything.

How do I remove an item from a list?

How do you remove multiple elements from a string array in Java?

Using List. removeIf():

  1. First Create an empty List of Array.
  2. Insert all elements of the array into the list.
  3. Remove all those element which is you want remove using equals() method.
  4. Convert the list back to an array and return its.