网上有关“java中super和this的区别”话题很是火热，小编也是针对java中super和this的区别寻找了一些与之相关的一些信息进行分析，如果能碰巧解决你现在面临的问题，希望能够帮助到您。
Java
1. super()?this()
This?,super?
Super,?
this?,.,super(),.?,(?private)..?this?,.
super?this.?super .2. ?public,protected,private,?
Public: ?
Private?
Protected:? ?
: ?3. ?
* * * * *
* * * *
* * *
* *
*
public class Print {
publicstatic void main(String[] args) {
for(int i = 0; i < 5; i++) {
for(int j = 5; j > i; j--) {
System.out.print("*");
}
System.out.println();
}
}
}
4. JAVA
Java?,?
null,
5. ?JAVA
break; return ?6. ?javajava(?)
:SerializableimplementsSerializable(FileOutputStream)?ObjectOutputStream(?)ObjectOutputStream?writeObject(Object obj)?obj?()
7. ".java"?
public?8. ?JAVA?
9. Overload?OverrideOverloaded
Override
Overloading
Java?
Overloaded?
1? public class Ctest(){
Public static void main(){
System.out.prinln(8+8+?88?+8+8);
}
} 168888
Overriding?Overloading?Java?Overriding?Overloading (Overriding)?(Overloading)?
Overloaded
10. Final?
?overridding
11. ,?,
:?package test;
public class FatherClass {
public FatherClass() {
System.out.println("FatherClassCreate");
}
}
:
package test;
import test.FatherClass;
public class ChildClass extends FatherClass{
public ChildClass() {
System.out.println("ChildClassCreate");
}
public static void main(String[] args) {
FatherClass fc = new FatherClass();
ChildClass cc = new ChildClass();
}
}
C:>java test.ChildClass
FatherClass Create
FatherClass Create
ChildClass Create
12. ?
package test;
public class OuterClass {
private class InterClass {
Public Interlass(){
System.out.println("InterClassCreate");
}
}
public OuterClass(){
InterClass ic = new InterClass();
System.out.println("OuterClassCreate");
}
public static void main(String[] args){
OuterClass oc = new OuterClass();
}
}
:
C:>java test/OuterClass InterClass Create OuterClass Create
13. ?JAVA?JAVA?()?
14. COLLECTION
15.
package test;
import java.util.*;
class InsertSort {
ArrayList al;
public InsertSort(int num,int mod) {
al = new ArrayList(num);
Random rand = new Random();
System.out.println("The ArrayList SortBefore:");
for (int i=0;i<num ;i++ ){
al.add(new Integer(Math.abs(rand.nextInt())% mod + 1));
System.out.println("al["+i+"]="+al.get(i));
}
}
public void SortIt(){
Integer tempInt;
int MaxSize=1;
for(int i=1;i<al.size();i++){
tempInt = (Integer)al.remove(i);
if(tempInt.intValue()>=((Integer)al.get(MaxSize-1)).intValue()){
al.add(MaxSize,tempInt);
MaxSize++;
System.out.println(al.toString());
} else {
for (int j=0;j<MaxSize ;j++ ){
if(((Integer)al.get(j)).intValue()>=tempInt.intValue()){
al.add(j,tempInt);
MaxSize++;
System.out.println(al.toString());
break;
}
}
}
}
System.out.println("The ArrayList SortAfter:");
for(int i=0;i<al.size();i++) {
System.out.println("al["+i+"]="+al.get(i));
}
}
public static void main(String[] args) {
InsertSort is = new InsertSort(10,100);
is.SortIt();
}
}
JAVAjava.io.Serializable
CollectionComparable ? Comparator
16. "?ABC"4?"?AB"?"?ABC?DEF"?6"?ABC"?"?ABC+"?
public static void split(String source,intnum) throws Exception{
intk=0;
Stringtemp="";
for(int i = 0; i <source.length(); i++){
byte[]b=(source.charAt(i)+"").getBytes();
k=k+b.length;
if(k>num){
break;
}
temp=temp+source.charAt(i);
}
System.out.println(temp);
}
15?Java,?
public class YesterdayCurrent{
public void main(String[] args){
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, -1);
System.out.println(cal.getTime());
}
}
16?,?
public int getNum(){
int i = -1;
try{
String stri="";
BufferedReader in = new BufferedReader(newFileReader(f));
while((stri=in.readLine())!=null){
i = Integer.parseInt(stri.trim());
}
in.close();
}catch(Exception e){
e.printStackTrace();
}
return i;
}
public void setNum(){
int i = getNum();
i++;
try{
PrintWriter out=new PrintWriter(newBufferedWriter(new FileWriter(f,false)));
out.write(String.valueOf(i)); //?intjava?windowsString
out.close() ;
}catch(Exception e){
e.printStackTrace();
}
}
17?
class A{
static{
System.out.print("1");
}
public A(){
System.out.print("2");
}
}
class B extends A{
static{
System.out.print("a");
}
public B(){
System.out.print("b");
}
}
public class Hello{
public static void main(String[] ars){
A ab = new B(); //?,: 1a2b
ab = new B(); //?,: 1a2b2b
}
}?:static ?,()?,?,?,?
18?
(1)?implements,extends(2),?(3):publicstatic final, "friendly"()
19?
(Class)?fields?method?construtor?interface?superClass?modified?Springstruts?hibernate20?
java.lang.Class?java.lang.refrection.Method?java.lang.refrection.Field java.lang.refrection.Constructor?java.lang.refrection.Modifier?java.lang.refrection.Interface21?Class?
.getClass().class?Integer.type(int) Integer.class(java.lang.Integer)?Class.forName();22?
Class?Class?Method?method.invoke(,?)23?Integer?Double
Integer.parseInt(?1234?) Double.parseDouble(?123.2?)
24
1+ 1.0+
25?
double d=1256.22d; d=d/100; System.out.println(Math.round(d)*100);
26
Calendar c=Calendar.getInstance();
c.set(Calendar.YEAR,2004);
c.set(Calendar.MONTH,0);
c.set(Calendar.DAY_OF_MONTH,31);
System.out.println(c.get(Calendar.YEAR)+" "+(c.get(Calendar.MONTH)+1)+" "+c.get(Calendar.DAY_OF_MONTH));
271970
Java.util.Date dat=new Date(); long now=dat.getTime();
System.currentTimeMillis()28
-1
public static void main(String[] args){
Calendarc=Calendar.getInstance();
c.set(Calendar.YEAR,2004);
c.set(Calendar.MONTH,0);
c.set(Calendar.DAY_OF_MONTH,30);
Calendarc1=(Calendar)c.clone();
System.out.println(c.get(Calendar.YEAR)+""+(c.get(Calendar.MONTH)+1)+" "+c.get(Calendar.DAY_OF_MONTH));
c.add(Calendar.DAY_OF_MONTH,1);
if(c.get(Calendar.MONTH)!=c1.get(Calendar.MONTH)){
System.out.println("?");
}else{
System.out.println("");
}
}
29?
Import java.text. SimpleDateFormat;
SimpleDateFormat sdf=newSimpleDateFormat("yyyy-MM-dd hh:mm:ss");
Date dat=new Date();
String str=sdf.format(dat); //?
System.out.println(str);
Java.util.Date d1=sdf.parse(?yyyy-mm-dd?); //?
30?GB2312?ISO-8859-1?
String a=new String("?".getBytes("gb2312"),"iso-8859-1");
String a=new String("?".getBytes("iso-8859-1"));
String a=new String("?".getBytes("gb2312"),"iso-8859-1");String a1=newString(a.getBytes("iso-8859-1"));
这里要说明一下，super和this的区别，this表示当前对象的指针(或叫引用)，super是一个java关键字，用于访问父类的成员和方法。所以调用的getClass()的确是父类方法，但是当前对象已经是子类了，而不是父类，你必须明白，super不代表父类对象。如果你想要得到父类对象，需要通过反射机制的到，代码如下：Classc=子类.class;c.getSuperclass().getName();这解释明白么？还有什么疑问？
关于“java中super和this的区别”这个话题的介绍，今天小编就给大家分享完了，如果对你有所帮助请保持对本站的关注！
本文来自作者[惜凡]投稿，不代表盛龙号立场，如若转载，请注明出处：https://snlon.net/sn/52207.html
评论列表（3条）
我是盛龙号的签约作者“惜凡”
本文概览：网上有关“java中super和this的区别”话题很是火热，小编也是针对java中super和this的区别寻找了一些与之相关的一些信息进行分析，如果能碰巧解决你现在面临的问...
文章不错《java中super和this的区别》内容很有帮助