,當它拋出java.lang.NullPointerException這裏是我的類,它需要測試:的JUnit測試:測試對字符串相關的setter和getter
public class RankingTableModel {
/**
* filePath stores the path of a csv file.
*/
private String filePath = "";
/**
* table data represents all the data in the table cells.
*/
private Object[][] table_data;
public String getFilePath() {
return filePath;
}
public void setFilePath (String filePath) {
this.filePath = filePath;
}
這裏是我的JUnit測試類(@Before, @After,.etc,我沒有做任何特別的事情,只是打印一些信息):
public class RankingTableModelTest {
private static final Object[][] data = {
{"US", new Integer(1), new Integer(2), new Integer(2),
new Integer(3)},
{"UK", new Integer(2), new Integer(2), new Integer(1),
new Integer(2)},
{"CHN", new Integer(3), new Integer(1), new Integer(3),
new Integer(1)},
};
private static final String file_path = "test";
private RankingTableModel test_model;
@Test
public void setFilePathAndGetFilePath() {
System.out.println("Testing setFilePath and getFilePath.");
test_model.setFilePath(file_path);
assertEquals(test_model.getFilePath(),"test");
}
}
當我運行測試,它拋出一個異常: java.lang.NullPointerExcepti at * .RankingTableModelTest.setFilePathAndGetFilePath(RankingTableModelTest.java:51) 51是行數:test_model.setFilePath(file_path);
我的代碼有什麼問題? Thx :)
非常感謝,它的工作原理:D – chygo