学步园

import java.util.ArrayList;<br /> import java.util.HashMap;<br /> import java.util.Map;<br /> import java.util.Vector;</p> <p>public class Test {<br /> private static int m_iNum = 0;<br /> private int mCount;</p> <p> public Test() {<br /> mCount = 0;<br /> m_iNum = 0;<br /> }</p> <p> public Test(int num) {<br /> mCount = 1;<br /> m_iNum = num;<br /> }</p> <p> public static void main(String argv[])<br /> {</p> <p> int arr1[] = {4, 5, 2, 1, 3, 9, 0, 7, 6, 8};</p> <p> System.out.println("/nmax number in arrray arr1 is:" + maxInt(arr1, arr1.length));</p> <p> Test sd = new Test();</p> <p> float f21 = 3; // ok<br /> // float f1 = 3.4; // ERROR! Type mismatch: cannot convert from double to float<br /> float f1 = 3.4f;<br /> float f3 = 3.4f;<br /> f3 = f3 + 1;</p> <p> int i = 0;<br /> ArrayList list = new ArrayList();<br /> Vector v = new Vector();<br /> while(i < 10) {<br /> list.add(i);<br /> list.add(i);<br /> v.add(i);<br /> i++;<br /> }</p> <p> System.out.println("ArrayList:");<br /> for(i = 0; i < list.size(); i++) {<br /> System.out.print(list.get(i) + ", ");<br /> }</p> <p> System.out.println("/nVector:");<br /> for(i = 0; i < v.size(); i++) {<br /> System.out.print(v.get(i) + ", ");<br /> }</p> <p> // 一个类集不能直接存储基本数据类型int，char，double等的值<br /> // ArrayList <int> mylist1 = new ArrayList <int>();<br /> ArrayList <int[]> mylist2 = new ArrayList <int[]>();<br /> ArrayList <String> mylist3 = new ArrayList <String>();<br /> ArrayList <Integer> mylist4 = new ArrayList <Integer>();</p> <p> Map<String, String> map1 = new HashMap<String, String>();<br /> Map<Integer, String> map2 = new HashMap<Integer, String>();<br /> for (int j = 0; j < 10; j++) {<br /> map2.put(j, "Hello " + j);<br /> }</p> <p> System.out.println();<br /> for(int j = 0; j < map2.size(); j++) {<br /> System.out.println(map2.get(j));<br /> }<br /> }</p> <p> public String toString()<br /> {<br /> System.out.println("BBB" + this.m_iNum);</p> <p> return "Z";<br /> }</p> <p> static void setInt(int i){<br /> i++;<br /> System.out.println("setInt(): i = " + i);<br /> }</p> <p> // 奇数在前，偶数在后<br /> public int[] fun(int[] arr) {<br /> int n = arr.length;<br /> int i = 0;<br /> int j = n - 1;</p> <p> while (i < j) {<br /> if (arr[i] % 2 != 0) { // odd number<br /> i++;<br /> } else { // even<br /> if (arr[j] % 2 != 0) {<br /> int temp = arr[i];<br /> arr[i] = arr[j];<br /> arr[j] = temp;<br /> }<br /> j--;<br /> }<br /> }</p> <p> return arr;<br /> }</p> <p> public static int maxInt(int[] arr, int n) {</p> <p> for(int i = 1; i < n; i++)<br /> {<br /> arr[0] = arr[i] > arr[0] ? arr[i]:arr[0];<br /> }</p> <p> return arr[0];<br /> }</p> <p> protected class Test1 extends Test{<br /> public Test1(int count) {<br /> setInt(0); // 非静态内部类可以访问外部类的静态和非静态成员函数<br /> toString();<br /> System.out.println("mCount = " + mCount); // 非静态内部类只能访问外部类的非静态成员变量<br /> }<br /> }</p> <p> static class Test2 extends Test{<br /> public Test2(int count) {<br /> setInt(0); // 静态内部类可以访问外部类的静态和非静态成员函数<br /> toString();<br /> System.out.println("m_iNum = " + m_iNum); // 静态内部类只能访问外部类的静态成员变量<br /> }<br /> }</p> <p>}<br />