Java internal class, float, arraylist, hashmap code example

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. P RINT (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> // a class set cannot directly store basic data types such as int, Char, values such as double <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/>}</P> <p> Public stri Ng 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> // the odd number is first, even number after <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/>}</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 ); // The non-static internal class can access the static and non-static member functions of the external class <br/> tostring (); <br/> system. out. println ("mcount =" + mcount ); // The non-static internal class can only access non-static member variables of the external class <br/>}</P> <p> static class Test2 extends test {<br /> Public Test2 (INT count) {<br/> setint (0); // static internal classes can access static and non-static member functions of external classes <br/> tostring (); <br/> system. out. println ("m_inum =" + m_inum ); // The static internal class can only access static member variables of the external class <br/>}</P> <p >}< br/>