使用testng执行测试时出现空指针异常

Question

//我试图通过使用testng

对它们进行分组来执行测试用例

                            package com.xyz.ngp.selenium;

            import org.testng.annotations.*;
            import javax.swing.*;
            import com.thoughtworks.selenium.SeleneseTestNgHelper;

            public class Grouping extends SeleneseTestNgHelper {

                @BeforeGroups (groups = {"smoke"})
                public void oneTimeSetUp() {          
                    try {           
                        String st="we are in BeforeGroups";
                        JOptionPane.showMessageDialog(null,st);
                        // scroll down to the bottom to see justprintsomething.
                        justprintsomething();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }       
                }

                @Test(groups = {"smoke"})
                public void test1() throws Exception {
                    String st="you wanted to execute smoke group";
                    JOptionPane.showMessageDialog(null,st);
                }

                @Test(groups = {"functional"})
                public void test2() throws Exception {
                    String st="you wanted to execute : either (functional) or this test: (test2)";
                    JOptionPane.showMessageDialog(null,st);
                }

                @Test(groups = {"test3"})
                public void test3() throws Exception {
                    String st="you wanted to execute : this test: (test3)";
                    JOptionPane.showMessageDialog(null,st);
                }

                //@BeforeMethod (groups = "smoke") //do i need this beforegroups here?
                public void justprintsomething() throws Exception  {          
                    try {           
                        // it gets printed 
                        String st="inside justprintsomething going to selenium.open";
                        JOptionPane.showMessageDialog(null,st);
                        // if i comment out the below line code works fine
                        selenium.open("http://www.google.com/");
                    } catch (Exception e) {
                        e.printStackTrace();
                    }       
                }

            }

//我在selenium.open之前收到空指针异常错误。

Answer 1

你从未初始化过selenium对象。