20175204 張湲禎 2018-2019-2《Java程序設計》
阿新 • • 發佈:2019-04-21
return 技術 技術分享 字符串拆分 binarys equals 拆分 inf exception
binarySearch
Arrays的binarySearch是尋找數組中某個元素所處的位置,其用法為(在arr中尋找數字1,將數字1的位置賦值給n,從0開始計數)
Arrays和String單元測試
一.類的作用
1.- String類
charAt
String的charAt的作用是將字符串中第i個位置上的字符(從0開始計數)賦值給n,其用法為n=string.charAt(i)
split
String的split的作用是將字符串拆分成為幾個字符串,其用法為(將字符串string以:為界限進行拆分,將拆分的幾個字符串賦值給字符串數組string1)string1=string.split(":")
2.- Arrays類
sort
Arrays的sort的作用是將數組中的元素從小到大排序,其用法為(對arr數組進行排序)Arrays.sort(arr);
binarySearch
Arrays的binarySearch是尋找數組中某個元素所處的位置,其用法為(在arr中尋找數字1,將數字1的位置賦值給n,從0開始計數)
n=Arrays.binarySearch(arr,1);
二.相關代碼
測試代碼
import junit.framework.TestCase; import org.junit.Test; import java.lang.*; import java.util.Arrays; public class ComplexTest extends TestCase { String str = "zyz is xinzhou huge"; String str2 = "zyz:is:xin:zhou:hu:ge"; String[] str3 = new String[]{ "1", "7", "5", "2", "0", "4"}; double str4[] = {2.0, 1.7, 5.2, 0.4, 66.6}; @Test public void testcharAt() throws Exception { assertEquals('z', Complex.getcharAt(str,0)); assertEquals('y', Complex.getcharAt(str,1)); assertEquals('z', Complex.getcharAt(str,2)); assertEquals('h', Complex.getcharAt(str,15)); assertEquals('g', Complex.getcharAt(str,17)); } @Test public void testsplit() throws Exception { assertEquals("zyz", Complex.getsplit(str2)[0]); assertEquals("hu", Complex.getsplit(str2)[4]); assertEquals("ge", Complex.getsplit(str2)[5]); } @Test public void testgetsort() throws Exception { //ArraysTest(str3); assertEquals("5", Complex.getsort(str3)[4]); assertEquals("2", Complex.getsort(str3)[2]); assertEquals("0", Complex.getsort(str3)[0]); assertEquals("4", Complex.getsort(str3)[3]); } @Test public void testgetbinarySearch() throws Exception { //ArraysTest2(str4); assertEquals(2, Arrays.binarySearch(Complex.getbinarySearch(str4), 2.0)); assertEquals(0, Arrays.binarySearch(Complex.getbinarySearch(str4), 0.4)); assertEquals(4, Arrays.binarySearch(Complex.getbinarySearch(str4), 66.6)); } }
import java.util.Arrays; public class Complex{ //測試charAt public static char charAt(String str, int i) { return str.charAt(i); } public static char getcharAt(String str, int i) { return charAt(str, i); } //測試split public static String[] split(String str) { String[] strsort = str.split(":"); return strsort; } public static String[] getsplit(String str) { return split(str); } //測試sort public static String[] sort(String[] str3) { Arrays.sort(str3); return str3; } public static String[] getsort(String[] str3) { return sort(str3); } //測試binarySearch public static double[] binarySearch(double[] str4) { Arrays.sort(str4); return str4; } public static double[] getbinarySearch(double[] str4) { return binarySearch(str4); } }
運行截圖
20175204 張湲禎 2018-2019-2《Java程序設計》