// Java Program to IllustrateAbstractClass// Main class// An abstract classabstractclassGFG{// Main driver methodpublicstaticvoidmain(String args[]){// Trying to create an objectGFG gfg =newGFG(); } } 输出: 观察6 类似的接口我们可以在抽象类中定义静态方法那可以在没有对象的情况下独立调用。
Traits 就像 Java 中的接口一样。但它们比 Java 中的接口更强大,因为在特征中我们可以实现成员。 例子: // Scala program to illustrate how to// create traits// traitstraitmytrait{// Abstract and non-abstract methoddefportaldeftutorial() { println("Scala tutorial") } }// GFG class extends trait...
// Java Program to Illustrate Methods // of AbstractSet class // Importing required classes importjava.util.*; // Main class publicclassGFG{ // Main driver method publicstaticvoidmain(String[]args)throwsException { // Try block to check for exceptions try{ // Creating an empty TreeSet of...
// Java program to illustrate isAbstract()importjava.lang.reflect.*;publicclassGFG{publicstaticvoidmain(String[]args){// get Method class objectMethod[]methods=Numbers.class.getMethods();// get Modifier Integer valueintmod1=methods[0].getModifiers();intmod2=methods[1].getModifiers();// check...
importjava.util.*; publicclassGfG{ publicstaticvoidmain(String[]args) { // Creating an instance of // the AbstractSequentialList AbstractSequentialList<Integer>absl =newLinkedList<>(); // adding elements to absl absl.add(5); absl.add(6); ...
// Java code to demonstrate the working of // clear() method in AbstractSequentialList import java.util.*; public class GFG { public static void main(String[] args) { // creating an AbstractSequentialList AbstractSequentialList arr = new LinkedList(); // using add() to initialize va...
deftutorial(){println("Scala tutorial")}}// GFG class extends traitclassGFGextendsmytrait{defportal(){println("Welcome!! GeeksforGeeks")}}objectMain{// Main methoddefmain(args:Array[String]){// object of GFG classvarobj=newGFG();obj.tutorial()obj.portal()}}// Output:// Scala tutorial...
Java // Java Program to Illustrate AbstractSetClass// Importing required classesimportjava.util.*;// Main classpublicclassGFG{// Main driver methodpublicstaticvoidmain(String[] args)throwsException{// Try block to check for exceptionstry{// Creating an empty TreeSet of integer type by// creati...
// Java code to demonstrate the working of//clear() method in AbstractSetimportjava.util.*;publicclassGFG{publicstaticvoidmain(String[] args){// creating an AbstractSetAbstractSet<Integer> arr =newTreeSet<Integer>();// using add() to initialize values// [1, 2, 3, 4]arr.add(1); ...
ClassCastException : 如果指定元素的类型与这个列表不兼容。 NullPointerException : 如果指定的元素是空的,而这个列表不允许空元素。 下面是说明lastIndexOf()方法的例子。 例1: // Java program to demonstrate lastIndexOf()// method for AbstractSequentialListimportjava.util.*;publicclassGFG{publicstati...