\u5b9a\u4e49：\u9690\u85cf\u5bf9\u8c61\u7684\u5c5e\u6027\u548c\u5b9e\u73b0\u7ec6\u8282，\u4ec5\u5bf9\u5916\u63d0\u4f9b\u516c\u5171\u8bbf\u95ee\u65b9\u5f0f\u3002
\n\u6838\u5fc3：\u5173\u6ce8\u201c\u5982\u4f55\u8c03\u7528\u201d，\u4e0d\u5173\u5fc3\u201c\u5185\u90e8\u5b9e\u73b0\u201d\u3002\u5c31\u50cf\u4f7f\u7528\u9065\u63a7\u5668，\u53ea\u9700\u77e5\u9053\u6309\u952e\u529f\u80fd，\u65e0\u9700\u4e86\u89e3\u5185\u90e8\u7535\u8def\u3002<\/p>\n
public class Person {
\n \/\/ 1. \u79c1\u6709\u5316\u5c5e\u6027
\n private String name;
\n private int age;<\/p>\n
\/\/ 2. \u63d0\u4f9b\u516c\u5171\u7684 Getter\/Setter
\n public String getName() {
\n return name;
\n }<\/p>\n
public void setName(String name) {
\n this.name = name;
\n }<\/p>\n
\/\/ Setter \u4e2d\u53ef\u4ee5\u52a0\u5165\u903b\u8f91\u6821\u9a8c，\u4fdd\u8bc1\u6570\u636e\u5b89\u5168
\n public void setAge(int age) {
\n if (age >= 0 && age <= 120) {
\n this.age = age;
\n } else {
\n System.out.println("\u5e74\u9f84\u4e0d\u5408\u6cd5！");
\n }
\n }
\n}<\/p>\n
\u95ee\u9898：\u5bf9\u4e8e\u5f15\u7528\u7c7b\u578b（\u5982 Date\u3001\u6570\u7ec4），\u5982\u679c get \u65b9\u6cd5\u76f4\u63a5\u8fd4\u56de\u5f15\u7528，\u5916\u90e8\u4ecd\u53ef\u4fee\u6539\u5bf9\u8c61\u5185\u90e8\u6570\u636e，\u5bfc\u81f4\u5c01\u88c5\u5931\u6548\u3002
\n\u89e3\u51b3：\u5728 get \u65b9\u6cd5\u4e2d\u8fd4\u56de\u5bf9\u8c61\u7684\u526f\u672c（\u6df1\u62f7\u8d1d）\u3002<\/p>\n
import java.util.Date;<\/p>\n
public class User {
\n private Date birthDate;<\/p>\n
\/\/ \u9519\u8bef\u7684 Getter (\u6d45\u62f7\u8d1d) – \u5916\u90e8\u53ef\u4fee\u6539 birthDate
\n \/\/ public Date getBirthDate() { return birthDate; }<\/p>\n
\/\/ \u6b63\u786e\u7684 Getter (\u6df1\u62f7\u8d1d) – \u8fd4\u56de\u526f\u672c
\n public Date getBirthDate() {
\n return new Date(birthDate.getTime());
\n }
\n}<\/p>\n
public class FinalDemo {
\n public static void main(String[] args) {
\n \/\/ 1. \u4fee\u9970\u57fa\u672c\u7c7b\u578b
\n final int NUM = 10;
\n \/\/ NUM = 20; \/\/ \u62a5\u9519：\u65e0\u6cd5\u518d\u6b21\u8d4b\u503c<\/p>\n
\/\/ 2. \u4fee\u9970\u5f15\u7528\u7c7b\u578b
\n final int[] arr = {1, 2, 3};
\n \/\/ arr = new int[5]; \/\/ \u62a5\u9519：\u5f15\u7528\u5730\u5740\u4e0d\u53ef\u53d8
\n arr[0] = 99; \/\/ \u6b63\u786e：\u5bf9\u8c61\u5185\u90e8\u5185\u5bb9\u53ef\u53d8
\n System.out.println(arr[0]); \/\/ \u8f93\u51fa 99
\n }
\n}<\/p>\n
\/\/ final class Father { } \/\/ \u62a5\u9519：\u65e0\u6cd5\u7ee7\u627f final \u7c7b<\/p>\n
class Father {
\n public final void run() {
\n System.out.println("\u7236\u4eb2\u5728\u8dd1");
\n }
\n}<\/p>\n
class Son extends Father {
\n \/\/ @Override
\n \/\/ public void run() { } \/\/ \u62a5\u9519：\u65e0\u6cd5\u91cd\u5199 final \u65b9\u6cd5
\n}<\/p>\n
public class StaticDemo {
\n static int staticVar = 1;
\n int instanceVar = 2;<\/p>\n
\/\/ \u9759\u6001\u65b9\u6cd5
\n public static void staticMethod() {
\n System.out.println(staticVar); \/\/ \u6b63\u786e
\n \/\/ System.out.println(instanceVar); \/\/ \u62a5\u9519：\u65e0\u6cd5\u8bbf\u95ee\u975e\u9759\u6001\u53d8\u91cf
\n }<\/p>\n
\/\/ \u975e\u9759\u6001\u65b9\u6cd5
\n public void instanceMethod() {
\n System.out.println(staticVar); \/\/ \u6b63\u786e
\n System.out.println(instanceVar); \/\/ \u6b63\u786e
\n }
\n}<\/p>\n
\u6838\u5fc3\u539f\u5219：Java \u4e2d\u53ea\u6709\u503c\u4f20\u9012\u3002<\/p>\n
public class PassByValueDemo {
\n \/\/ \u57fa\u672c\u7c7b\u578b\u4f20\u9012
\n public static void changeValue(int x) {
\n x = 100; \/\/ \u4fee\u6539\u526f\u672c，\u4e0d\u5f71\u54cd main \u4e2d\u7684 a
\n }<\/p>\n
\/\/ \u5f15\u7528\u7c7b\u578b\u4f20\u9012
\n public static void changeObj(Person p) {
\n p.setName("\u674e\u56db"); \/\/ \u4fee\u6539\u526f\u672c\u6307\u5411\u7684\u5bf9\u8c61\u5185\u5bb9，\u5f71\u54cd main \u4e2d\u7684 person
\n p = new Person(); \/\/ \u4fee\u6539\u526f\u672c\u7684\u6307\u5411，\u4e0d\u5f71\u54cd main \u4e2d\u7684 person
\n p.setName("\u738b\u4e94");
\n }<\/p>\n
public static void main(String[] args) {
\n int a = 10;
\n changeValue(a);
\n System.out.println(a); \/\/ \u8f93\u51fa 10<\/p>\n
Person person = new Person("\u5f20\u4e09");
\n changeObj(person);
\n System.out.println(person.getName()); \/\/ \u8f93\u51fa "\u674e\u56db"，\u4e0d\u662f "\u738b\u4e94"
\n }
\n}<\/p>\n
\u5728\u540c\u4e00\u4e2a\u7c7b\u4e2d，\u5141\u8bb8\u5b58\u5728\u591a\u4e2a\u540c\u540d\u65b9\u6cd5，\u4f46\u53c2\u6570\u5217\u8868\u5fc5\u987b\u4e0d\u540c（\u7c7b\u578b\u3001\u6570\u91cf\u3001\u987a\u5e8f）\u3002<\/p>\n
public class OverloadDemo {
\n \/\/ \u53c2\u6570\u7c7b\u578b\u4e0d\u540c
\n public void add(int a, int b) { System.out.println("\u6574\u6570\u76f8\u52a0"); }
\n public void add(double a, double b) { System.out.println("\u5c0f\u6570\u76f8\u52a0"); }<\/p>\n
\/\/ \u53c2\u6570\u6570\u91cf\u4e0d\u540c
\n public void add(int a) { System.out.println("\u5355\u4e2a\u6574\u6570"); }<\/p>\n
\/\/ \u53c2\u6570\u987a\u5e8f\u4e0d\u540c
\n public void print(String s, int i) { }
\n public void print(int i, String s) { }<\/p>\n
\/\/ public int add(int a, int b) { } \/\/ \u62a5\u9519：\u4e0e\u7b2c\u4e00\u4e2a\u65b9\u6cd5\u7b7e\u540d\u51b2\u7a81
\n}<\/p>\n
\u5982\u679c\u6210\u5458\u53d8\u91cf\u672a\u663e\u5f0f\u8d4b\u503c，\u7cfb\u7edf\u4f1a\u8d4b\u4e88\u9ed8\u8ba4\u503c（int\u4e3a0，boolean\u4e3afalse，\u5f15\u7528\u4e3anull）\u3002<\/p>\n
\u5728\u6784\u9020\u5668\u4e2d\u8c03\u7528\u672c\u7c7b\u7684\u5176\u4ed6\u6784\u9020\u5668，\u5fc5\u987b\u653e\u5728\u7b2c\u4e00\u884c\u3002<\/p>\n
public class Person {
\n private String name;
\n private int age;<\/p>\n
\/\/ \u65e0\u53c2\u6784\u9020
\n public Person() {
\n this("\u533f\u540d", 18); \/\/ \u8c03\u7528\u6709\u53c2\u6784\u9020，\u5fc5\u987b\u5199\u5728\u7b2c\u4e00\u884c
\n }<\/p>\n
\/\/ \u6709\u53c2\u6784\u9020
\n public Person(String name, int age) {
\n this.name = name;
\n this.age = age;
\n }
\n}<\/p>\n
\u4f7f\u7528 {} \u5305\u88f9\u7684\u4ee3\u7801\u5757，\u7528\u4e8e\u521d\u59cb\u5316\u5c5e\u6027\u3002<\/p>\n
public class InitDemo {
\n static {
\n System.out.println("1. \u9759\u6001\u4ee3\u7801\u5757");
\n }<\/p>\n
{
\n System.out.println("2. \u666e\u901a\u4ee3\u7801\u5757");
\n }<\/p>\n
public InitDemo() {
\n System.out.println("3. \u6784\u9020\u5668");
\n }<\/p>\n
public static void main(String[] args) {
\n new InitDemo();
\n new InitDemo();
\n }
\n}
\n\/\/ \u8f93\u51fa：
\n\/\/ 1. \u9759\u6001\u4ee3\u7801\u5757
\n\/\/ 2. \u666e\u901a\u4ee3\u7801\u5757
\n\/\/ 3. \u6784\u9020\u5668
\n\/\/ 2. \u666e\u901a\u4ee3\u7801\u5757
\n\/\/ 3. \u6784\u9020\u5668<\/p>\n
class Animal {
\n public void run() { System.out.println("\u52a8\u7269\u8dd1"); }
\n}<\/p>\n
class Dog extends Animal {
\n @Override
\n public void run() { System.out.println("\u72d7\u8dd1"); } \/\/ \u91cd\u5199
\n}<\/p>\n
public class PolyDemo {
\n public static void main(String[] args) {
\n Animal a = new Dog(); \/\/ \u591a\u6001
\n a.run(); \/\/ \u8f93\u51fa "\u72d7\u8dd1"，\u6267\u884c\u5b50\u7c7b\u91cd\u5199\u7684\u65b9\u6cd5<\/p>\n
\/\/ a.bark(); \/\/ \u62a5\u9519：Animal \u7c7b\u4e2d\u6ca1\u6709 bark \u65b9\u6cd5
\n }
\n}<\/p>\n
Animal a = new Dog();
\nDog d = (Dog) a; \/\/ \u5f3a\u5236\u8f6c\u6362
\nd.bark(); \/\/ \u8c03\u7528\u5b50\u7c7b\u7279\u6709\u65b9\u6cd5<\/p>\n
\u5b50\u7c7b\u7ee7\u627f\u7236\u7c7b\u4e4b\u540e\u53ef\u4ee5\u7528\u7236\u7c7b\u7684\u6240\u4ee5\u65b9\u6cd5（\u91cd\u5199\u8fc7\u7684\u5c31\u6309\u7167\u81ea\u5df1\u7684\u65b9\u6cd5\u8fd0\u884c）\u548c\u81ea\u5df1\u7684\u65b9\u6cd5\u3002\u7236\u7c7b\u4e0d\u80fd\u7528\u5b50\u7c7b\u7684\u65b9\u6cd5\u3002\u7236\u7c7b\u5f3a\u5236\u8f6c\u5316\u4e3a\u5b50\u7c7b\u65f6\u53ef\u4ee5\u7528\u81ea\u5df1\u7684\u65b9\u6cd5\u548c\u5b50\u7c7b\u91cd\u5199\u7684\u65b9\u6cd5\u3002\u7236\u7c7b\u53ef\u4ee5\u4f7f\u7528\u5b50\u7c7b\u5b9a\u4e49\u7684\u6240\u6709\u6570\u636e\u7c7b\u578b\u3002<\/p>\n
\u5f53\u6d89\u53ca\u7ee7\u627f\u65f6，\u521d\u59cb\u5316\u987a\u5e8f\u5982\u4e0b：<\/p>\n
\u53e3\u8bc0：\u9759\u7236 -> \u9759\u5b50 -> \u666e\u7236 -> \u6784\u7236 -> \u666e\u5b50 -> \u6784\u5b50<\/p>\n
class Father {
\n static { System.out.println("1. \u7236\u7c7b\u9759\u6001"); }
\n { System.out.println("3. \u7236\u7c7b\u666e\u901a"); }
\n public Father() { System.out.println("4. \u7236\u7c7b\u6784\u9020"); }
\n}<\/p>\n
class Son extends Father {
\n static { System.out.println("2. \u5b50\u7c7b\u9759\u6001"); }
\n { System.out.println("5. \u5b50\u7c7b\u666e\u901a"); }
\n public Son() { System.out.println("6. \u5b50\u7c7b\u6784\u9020"); }
\n}<\/p>\n
public class Test {
\n public static void main(String[] args) {
\n new Son();
\n }
\n}<\/p>\n
Java\u901a\u8fc7\u56db\u79cd\u6743\u9650\u63a7\u5236\u7c7b\u6210\u5458\u7684\u53ef\u89c1\u6027\u3002<\/p>\n
| public<\/td>\n | \u2705<\/td>\n | \u2705<\/td>\n | \u2705<\/td>\n | \u2705<\/td>\n | \u516c\u5f00：\u5927\u95e8\u655e\u5f00，\u8c01\u90fd\u80fd\u8fdb\u3002<\/td>\n<\/tr>\n |
| protected<\/td>\n | \u2705<\/td>\n | \u2705<\/td>\n | \u2705<\/td>\n | \u274c<\/td>\n | \u53d7\u4fdd\u62a4：\u540c\u5305\u90bb\u5c45\u80fd\u8fdb，\u4e0d\u540c\u5305\u7684\u4eb2\u621a（\u5b50\u7c7b）\u4e5f\u80fd\u8fdb\u3002<\/td>\n<\/tr>\n |
| (\u9ed8\u8ba4)<\/td>\n | \u2705<\/td>\n | \u2705<\/td>\n | \u274c<\/td>\n | \u274c<\/td>\n | \u5305\u7ea7\u79c1\u6709：\u4ec5\u9650\u540c\u5305\u90bb\u5c45，\u8de8\u5305\u5373\u4f7f\u662f\u4eb2\u621a\u4e5f\u4e0d\u884c\u3002<\/td>\n<\/tr>\n |
| private<\/td>\n | \u2705<\/td>\n | \u274c<\/td>\n | \u274c<\/td>\n | \u274c<\/td>\n | \u79c1\u6709：\u4ec5\u9650\u81ea\u5df1，\u8c01\u90fd\u4e0d\u8ba9\u8fdb\u3002<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n class Person { public void test() { \n 12. \u62bd\u8c61\u7c7b (Abstract Class)<\/h4>\n
|