{"id":231,"date":"2026-07-16T13:27:21","date_gmt":"2026-07-16T05:27:21","guid":{"rendered":"http:\/\/ssjava.xyz\/?p=231"},"modified":"2026-07-17T11:08:34","modified_gmt":"2026-07-17T03:08:34","slug":"12-%e5%8c%85%e3%80%81%e8%ae%bf%e9%97%ae%e6%9d%83%e9%99%90%e3%80%81static-%e4%b8%8e%e7%bb%bc%e5%90%88%e5%ae%9e%e6%88%98","status":"publish","type":"post","link":"https:\/\/ssjava.xyz\/index.php\/2026\/07\/16\/12-%e5%8c%85%e3%80%81%e8%ae%bf%e9%97%ae%e6%9d%83%e9%99%90%e3%80%81static-%e4%b8%8e%e7%bb%bc%e5%90%88%e5%ae%9e%e6%88%98\/","title":{"rendered":"12. \u5305\u3001\u8bbf\u95ee\u6743\u9650\u3001static \u4e0e\u7efc\u5408\u5b9e\u6218"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u524d\u4e24\u7bc7\u6587\u7ae0\u6211\u4eec\u5b66\u4f1a\u4e86\u7c7b\u7684\u5b9a\u4e49\u3001\u5c01\u88c5\u3001\u6784\u9020\u5668\u3002\u4f46\u4e00\u4e2a\u771f\u5b9e\u7684 Java \u9879\u76ee\u901a\u5e38\u6709\u6210\u767e\u4e0a\u5343\u4e2a\u7c7b\u2014\u2014\u5b83\u4eec\u600e\u4e48\u7ec4\u7ec7\uff1f\u7c7b\u4e0e\u7c7b\u4e4b\u95f4\u7684\u8bbf\u95ee\u8fb9\u754c\u5728\u54ea\u91cc\uff1f\u6709\u6ca1\u6709\u4e00\u4e9b&#8221;\u5c5e\u4e8e\u7c7b\u672c\u8eab\u800c\u4e0d\u662f\u5bf9\u8c61&#8221;\u7684\u6210\u5458\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u7bc7\u6587\u7ae0\u5c31\u6765\u56de\u7b54\u8fd9\u4e09\u4e2a\u95ee\u9898\uff0c\u6700\u540e\u7528\u4e00\u4e2a\u7efc\u5408\u6848\u4f8b\u628a\u672c\u9636\u6bb5\u7684\u77e5\u8bc6\u5168\u90e8\u4e32\u8d77\u6765\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e00\u3001\u5305\uff08Package\uff09\uff1a\u7c7b\u7684\u7ec4\u7ec7\u65b9\u5f0f<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1.1 \u4e3a\u4ec0\u4e48\u9700\u8981\u5305\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u60f3\u8c61\u4e00\u4e0b\uff0c\u4e00\u4e2a\u9879\u76ee\u4e2d\u6709 300 \u4e2a Java \u7c7b\uff1a <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u547d\u540d\u51b2\u7a81<\/strong>\uff1a\u9879\u76ee\u4e2d\u6709\u4e00\u4e2a <code>User<\/code> \u7c7b\uff0c\u5f15\u7528\u7684\u7b2c\u4e09\u65b9\u5e93\u4e5f\u6709\u4e00\u4e2a <code>User<\/code> \u7c7b\u2014\u2014\u600e\u4e48\u529e\uff1f<\/li>\n\n\n\n<li><strong>\u7ec4\u7ec7\u6df7\u4e71<\/strong>\uff1a\u6240\u6709 Java \u6587\u4ef6\u5806\u5728\u4e00\u4e2a\u76ee\u5f55\u91cc\uff0c\u627e\u8d77\u6765\u50cf\u5927\u6d77\u635e\u9488\u3002<\/li>\n\n\n\n<li><strong>\u8bbf\u95ee\u63a7\u5236<\/strong>\uff1a\u600e\u4e48\u533a\u5206&#8221;\u5185\u90e8\u5de5\u5177\u7c7b&#8221;\u548c&#8221;\u5bf9\u5916\u66b4\u9732\u7684 API&#8221;\uff1f<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u5305<\/strong>\uff08Package\uff09\u5c31\u662f Java \u89e3\u51b3\u8fd9\u4e9b\u95ee\u9898\u7684\u65b9\u5f0f\u2014\u2014\u5b83\u5c31\u50cf\u6587\u4ef6\u7cfb\u7edf\u4e2d\u7684\u6587\u4ef6\u5939\uff0c\u4e3a\u7c7b\u63d0\u4f9b\u4e86\u540d\u5b57\u7a7a\u95f4\u548c\u7ec4\u7ec7\u7ed3\u6784\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1.2 \u5305\u7684\u547d\u540d\u89c4\u8303<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Java \u5305\u7684\u547d\u540d\u4f7f\u7528<strong>\u5012\u7f6e\u7684\u57df\u540d<\/strong>\u4f5c\u4e3a\u524d\u7f00\uff0c\u786e\u4fdd\u5168\u7403\u552f\u4e00\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>com.\u516c\u53f8\u540d.\u9879\u76ee\u540d.\u6a21\u5757\u540d\norg.apache.commons.lang3\njava.util\njavax.servlet<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u5305\u540d\u5168\u90e8\u5c0f\u5199\uff0c\u7528\u70b9\u53f7\u5206\u9694\u5c42\u7ea7\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1.3 \u4f7f\u7528\u5305<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5b9a\u4e49\u4e00\u4e2a\u7c7b\u6240\u5728\u7684\u5305\uff1a<\/p>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">package com.ssjava.oop.model;\n\npublic class Student {\n    \/\/ \u7c7b\u7684\u5b9a\u4e49...\n}<\/code><\/pre>\n\n\n<p class=\"wp-block-paragraph\">\u5f15\u7528\u5176\u4ed6\u5305\u4e2d\u7684\u7c7b\uff1a<\/p>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">\/\/ \u65b9\u5f0f\u4e00\uff1a\u4f7f\u7528\u5b8c\u6574\u9650\u5b9a\u540d\ncom.ssjava.oop.model.Student s = new com.ssjava.oop.model.Student();\n\/\/ \u592a\u957f\u4e86\uff0c\u4e0d\u63a8\u8350\n\n\/\/ \u65b9\u5f0f\u4e8c\uff1a\u4f7f\u7528 import \u5bfc\u5165\uff08\u63a8\u8350\uff09\nimport com.ssjava.oop.model.Student;\n\/\/ \u6216\u5bfc\u5165\u6574\u4e2a\u5305\u4e0b\u7684\u6240\u6709\u7c7b\nimport com.ssjava.oop.model.*;\n\npublic class Test {\n    public static void main(String[] args) {\n        Student s = new Student();  \/\/ \u7b80\u6d01\u591a\u4e86\n    }\n}<\/code><\/pre>\n\n\n<p class=\"wp-block-paragraph\"><strong>\u91cd\u8981<\/strong>\uff1a<code>java.lang<\/code> \u5305\u4e0b\u7684\u7c7b\uff08\u5982 <code>String<\/code>\u3001<code>System<\/code>\u3001<code>Math<\/code>\uff09\u4f1a\u81ea\u52a8\u5bfc\u5165\uff0c\u4e0d\u9700\u8981\u5199 import\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1.4 \u5305\u76ee\u5f55\u7ed3\u6784<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5305\u540d <code>com.ssjava.oop.model<\/code> \u5bf9\u5e94\u6587\u4ef6\u76ee\u5f55 <code>com\/ssjava\/oop\/model\/<\/code>\uff0c\u8fd9\u662f Java \u7684\u786c\u6027\u8981\u6c42\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>src\/\n \u2514\u2500\u2500 com\/\n      \u2514\u2500\u2500 ssjava\/\n           \u2514\u2500\u2500 oop\/\n                \u251c\u2500\u2500 model\/\n                \u2502    \u251c\u2500\u2500 Student.java\n                \u2502    \u2514\u2500\u2500 Teacher.java\n                \u251c\u2500\u2500 service\/\n                \u2502    \u251c\u2500\u2500 StudentService.java\n                \u2502    \u2514\u2500\u2500 TeacherService.java\n                \u2514\u2500\u2500 Main.java<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e8c\u3001\u56de\u987e\u4e0e\u6df1\u5316\uff1a\u8bbf\u95ee\u4fee\u9970\u7b26<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u4e00\u7bc7\u6587\u7ae0\u6211\u4eec\u4ecb\u7ecd\u4e86\u8bbf\u95ee\u4fee\u9970\u7b26\uff0c\u73b0\u5728\u628a\u5b83\u8ddf\u5305\u7684\u6982\u5ff5\u653e\u5728\u4e00\u8d77\u770b\uff0c\u7406\u89e3\u4f1a\u66f4\u900f\u5f7b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>\u4fee\u9970\u7b26<\/th><th>\u672c\u7c7b<\/th><th>\u540c\u5305<\/th><th>\u4e0d\u540c\u5305\u5b50\u7c7b<\/th><th>\u4e0d\u540c\u5305\u975e\u5b50\u7c7b<\/th><\/tr><\/thead><tbody><tr><td><code>private<\/code><\/td><td>\u2705<\/td><td>\u274c<\/td><td>\u274c<\/td><td>\u274c<\/td><\/tr><tr><td><code>\u9ed8\u8ba4\uff08default\uff09<\/code><\/td><td>\u2705<\/td><td>\u2705<\/td><td>\u274c<\/td><td>\u274c<\/td><\/tr><tr><td><code>protected<\/code><\/td><td>\u2705<\/td><td>\u2705<\/td><td>\u2705<\/td><td>\u274c<\/td><\/tr><tr><td><code>public<\/code><\/td><td>\u2705<\/td><td>\u2705<\/td><td>\u2705<\/td><td>\u2705<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u5b9e\u7528\u5efa\u8bae\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5c5e\u6027\u4e00\u5f8b private<\/strong>\uff1a\u5c01\u88c5\u7684\u6838\u5fc3\u539f\u5219<\/li>\n\n\n\n<li><strong>\u516c\u5f00\u65b9\u6cd5\u7528 public<\/strong>\uff1a\u5bf9\u5916\u63d0\u4f9b API<\/li>\n\n\n\n<li><strong>\u5185\u90e8\u8f85\u52a9\u65b9\u6cd5\u7528 private<\/strong>\uff1a\u4e0d\u5bf9\u5916\u66b4\u9732\u7684\u7ec6\u8282<\/li>\n\n\n\n<li><strong>\u540c\u4e00\u5305\u5185\u534f\u4f5c\u7528 default<\/strong>\uff1a\u6bd4\u5982\u540c\u4e00\u4e2a\u6a21\u5757\u5185\u7c7b\u4e4b\u95f4<\/li>\n\n\n\n<li><strong>\u7559\u7ed9\u5b50\u7c7b\u6269\u5c55\u7528 protected<\/strong>\uff1a\u4ec5\u5728\u660e\u786e\u9700\u8981\u5b50\u7c7b\u8bbf\u95ee\u65f6\u624d\u7528<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e09\u3001static \u5173\u952e\u5b57\uff1a\u5c5e\u4e8e\u7c7b\u7684\u6210\u5458<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">3.1 \u9759\u6001\u5c5e\u6027\uff08\u7c7b\u53d8\u91cf\uff09<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u5e38\u60c5\u51b5\u4e0b\uff0c\u5c5e\u6027\u5c5e\u4e8e<strong>\u5bf9\u8c61\u5b9e\u4f8b<\/strong>\u2014\u2014\u6bcf\u4e2a\u5bf9\u8c61\u6709\u81ea\u5df1\u7684\u526f\u672c\u3002\u4f46\u6709\u4e9b\u6570\u636e\u5e94\u8be5\u88ab\u6240\u6709\u5bf9\u8c61<strong>\u5171\u4eab<\/strong>\uff1a<\/p>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">public class Student {\n    private String name;\n    private int age;\n    \n    \/\/ \u9759\u6001\u53d8\u91cf\uff1a\u6240\u6709\u5bf9\u8c61\u5171\u4eab\n    private static String schoolName = \"SSJava \u5b66\u9662\";\n    private static int studentCount = 0;  \/\/ \u8bb0\u5f55\u5b66\u751f\u603b\u6570\n    \n    public Student(String name, int age) {\n        this.name = name;\n        this.age = age;\n        studentCount++;  \/\/ \u6bcf\u521b\u5efa\u4e00\u4e2a\u5b66\u751f\uff0c\u603b\u6570+1\n    }\n    \n    \/\/ \u9759\u6001\u65b9\u6cd5\n    public static int getStudentCount() {\n        return studentCount;\n    }\n    \n    public static String getSchoolName() {\n        return schoolName;\n    }\n    \n    public void showInfo() {\n        System.out.println(\"\u5b66\u6821\uff1a\" + schoolName + \"\uff0c\u59d3\u540d\uff1a\" + name + \"\uff0c\u5e74\u9f84\uff1a\" + age);\n    }\n}<\/code><\/pre>\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528\u9759\u6001\u6210\u5458\uff1a<\/p>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">public class TestStudent {\n    public static void main(String[] args) {\n        \/\/ \u9759\u6001\u6210\u5458\u901a\u8fc7\u7c7b\u540d\u76f4\u63a5\u8bbf\u95ee\uff0c\u4e0d\u9700\u8981\u5bf9\u8c61\n        System.out.println(Student.getSchoolName());  \/\/ SSJava \u5b66\u9662\n        \n        Student s1 = new Student(\"\u5f20\u4e09\", 20);\n        Student s2 = new Student(\"\u674e\u56db\", 22);\n        Student s3 = new Student(\"\u738b\u4e94\", 19);\n        \n        s1.showInfo();\n        s2.showInfo();\n        s3.showInfo();\n        \n        \/\/ \u6240\u6709\u5bf9\u8c61\u5171\u4eab\u540c\u4e00\u4e2a\u8ba1\u6570\n        System.out.println(\"\u5b66\u751f\u603b\u6570\uff1a\" + Student.getStudentCount());  \/\/ 3\n    }\n}<\/code><\/pre>\n\n\n<h3 class=\"wp-block-heading\">3.2 \u9759\u6001\u65b9\u6cd5\u7684\u7279\u70b9<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u901a\u8fc7<strong>\u7c7b\u540d<\/strong>\u76f4\u63a5\u8c03\u7528\uff0c\u4e0d\u9700\u8981\u521b\u5efa\u5bf9\u8c61<\/li>\n\n\n\n<li><strong>\u4e0d\u80fd\u76f4\u63a5\u8bbf\u95ee\u975e\u9759\u6001\u6210\u5458<\/strong>\uff08\u9759\u6001\u65b9\u6cd5\u4e2d\u4e0d\u80fd\u7528 <code>this<\/code>\uff0c\u56e0\u4e3a\u8fd8\u6ca1\u6709\u5bf9\u8c61\uff09<\/li>\n\n\n\n<li>\u9759\u6001\u65b9\u6cd5\u53ea\u80fd\u8c03\u7528\u5176\u4ed6\u9759\u6001\u65b9\u6cd5\/\u5c5e\u6027<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f60\u6bcf\u5929\u90fd\u5728\u7528\u9759\u6001\u65b9\u6cd5\u2014\u2014<code>System.out.println()<\/code>\u3001<code>Math.max()<\/code>\u3001<code>Integer.parseInt()<\/code> \u90fd\u662f\u9759\u6001\u65b9\u6cd5\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">3.3 \u9759\u6001\u4ee3\u7801\u5757<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u6709\u65f6\u5019\u6211\u4eec\u9700\u8981\u5728\u7c7b\u52a0\u8f7d\u65f6\u6267\u884c\u4e00\u4e9b\u521d\u59cb\u5316\u64cd\u4f5c\uff0c\u6bd4\u5982\u8bfb\u53d6\u914d\u7f6e\u6587\u4ef6\u3002\u9759\u6001\u4ee3\u7801\u5757\u5c31\u662f\u5e72\u8fd9\u4e2a\u7684\uff1a<\/p>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">public class Config {\n    private static String dbUrl;\n    private static String username;\n    private static String password;\n    \n    \/\/ \u9759\u6001\u4ee3\u7801\u5757\uff1a\u7c7b\u52a0\u8f7d\u65f6\u6267\u884c\u4e00\u6b21\n    static {\n        System.out.println(\"Config \u7c7b\u6b63\u5728\u521d\u59cb\u5316...\");\n        dbUrl = \"jdbc:mysql:\/\/localhost:3306\/ssjava\";\n        username = \"root\";\n        password = \"secret\";\n    }\n    \n    public static void showConfig() {\n        System.out.println(\"\u6570\u636e\u5e93 URL\uff1a\" + dbUrl);\n        System.out.println(\"\u7528\u6237\u540d\uff1a\" + username);\n    }\n    \n    public static void main(String[] args) {\n        Config.showConfig();  \/\/ \u9759\u6001\u4ee3\u7801\u5757\u5728\u7b2c\u4e00\u6b21\u8bbf\u95ee\u7c7b\u65f6\u6267\u884c\n    }\n}<\/code><\/pre>\n\n\n<p class=\"wp-block-paragraph\">\u8f93\u51fa\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Config \u7c7b\u6b63\u5728\u521d\u59cb\u5316...\n\u6570\u636e\u5e93 URL\uff1ajdbc:mysql:\/\/localhost:3306\/ssjava\n\u7528\u6237\u540d\uff1aroot<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6267\u884c\u987a\u5e8f\uff1a<strong>\u9759\u6001\u4ee3\u7801\u5757 \u2192 \u6784\u9020\u4ee3\u7801\u5757\uff08\u540e\u9762\u4f1a\u8bb2\uff09\u2192 \u6784\u9020\u5668<\/strong>\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u56db\u3001\u7efc\u5408\u6848\u4f8b\uff1a\u5728\u7ebf\u4e66\u5e97\u7cfb\u7edf<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u73b0\u5728\u6211\u4eec\u628a\u524d\u9762\u4e09\u7bc7\u6587\u7ae0\u7684\u6240\u6709\u77e5\u8bc6\u6574\u5408\u8d77\u6765\uff0c\u8bbe\u8ba1\u4e00\u4e2a\u7b80\u5355\u7684\u5728\u7ebf\u4e66\u5e97\u7cfb\u7edf\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">4.1 \u56fe\u4e66\u7c7b\uff08Book\uff09<\/h3>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">public class Book {\n    private String isbn;        \/\/ \u4e66\u53f7\n    private String title;       \/\/ \u4e66\u540d\n    private String author;      \/\/ \u4f5c\u8005\n    private double price;       \/\/ \u5355\u4ef7\n    private int stock;          \/\/ \u5e93\u5b58\n    \n    \/\/ \u9759\u6001\u53d8\u91cf\uff1a\u56fe\u4e66\u603b\u6570\u548c\u603b\u6536\u5165\n    private static int totalBooks = 0;\n    private static double totalRevenue = 0;\n    \n    public Book() {\n        this(\"\u672a\u77e5\", \"\u672a\u77e5\", \"\u672a\u77e5\", 0, 0);\n    }\n    \n    public Book(String isbn, String title, String author, double price, int stock) {\n        this.isbn = isbn;\n        this.title = title;\n        this.author = author;\n        setPrice(price);        \/\/ \u590d\u7528\u6821\u9a8c\u903b\u8f91\n        setStock(stock);\n    }\n    \n    \/\/ getter \/ setter \u5e26\u6821\u9a8c\n    public String getIsbn() { return isbn; }\n    public String getTitle() { return title; }\n    public String getAuthor() { return author; }\n    \n    public double getPrice() { return price; }\n    \n    public void setPrice(double price) {\n        if (price &lt; 0) {\n            System.out.println(&quot;\u4ef7\u683c\u4e0d\u80fd\u4e3a\u8d1f\u6570\uff01&quot;);\n            return;\n        }\n        this.price = price;\n    }\n    \n    public int getStock() { return stock; }\n    \n    public void setStock(int stock) {\n        if (stock &lt; 0) {\n            System.out.println(&quot;\u5e93\u5b58\u4e0d\u80fd\u4e3a\u8d1f\u6570\uff01&quot;);\n            return;\n        }\n        this.stock = stock;\n    }\n    \n    \/\/ \u552e\u51fa\u4e00\u672c\u4e66\n    public boolean sell(int quantity) {\n        if (quantity  stock) {\n            System.out.println(\"\u5e93\u5b58\u4e0d\u8db3\uff01\u5f53\u524d\u5e93\u5b58\uff1a\" + stock);\n            return false;\n        }\n        stock -= quantity;\n        double income = price * quantity;\n        totalRevenue += income;\n        totalBooks += quantity;\n        System.out.println(\"\u552e\u51fa\u300a\" + title + \"\u300b\u00d7\" + quantity + \"\uff0c\u6536\u5165 \" + income + \" \u5143\");\n        return true;\n    }\n    \n    public void showInfo() {\n        System.out.println(\"===== \u56fe\u4e66\u4fe1\u606f =====\");\n        System.out.println(\"\u4e66\u53f7\uff1a\" + isbn);\n        System.out.println(\"\u4e66\u540d\uff1a\u300a\" + title + \"\u300b\");\n        System.out.println(\"\u4f5c\u8005\uff1a\" + author);\n        System.out.println(\"\u5b9a\u4ef7\uff1a\" + price + \" \u5143\");\n        System.out.println(\"\u5e93\u5b58\uff1a\" + stock + \" \u672c\");\n        System.out.println(\"===================\");\n    }\n    \n    \/\/ \u9759\u6001\u65b9\u6cd5\n    public static int getTotalBooks() {\n        return totalBooks;\n    }\n    \n    public static double getTotalRevenue() {\n        return totalRevenue;\n    }\n}<\/code><\/pre>\n\n\n<h3 class=\"wp-block-heading\">4.2 \u987e\u5ba2\u7c7b\uff08Customer\uff09<\/h3>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">public class Customer {\n    private String id;\n    private String name;\n    private String phone;\n    private double balance;          \/\/ \u8d26\u6237\u4f59\u989d\n    private static int customerCount = 0;\n    \n    public Customer(String id, String name, String phone, double balance) {\n        this.id = id;\n        this.name = name;\n        this.phone = phone;\n        this.balance = balance;\n        customerCount++;\n    }\n    \n    public String getId() { return id; }\n    public String getName() { return name; }\n    public String getPhone() { return phone; }\n    public double getBalance() { return balance; }\n    \n    \/\/ \u5145\u503c\n    public void recharge(double amount) {\n        if (amount &lt;= 0) {\n            System.out.println(&quot;\u5145\u503c\u91d1\u989d\u5fc5\u987b\u5927\u4e8e0&quot;);\n            return;\n        }\n        balance += amount;\n        System.out.println(name + &quot; \u5145\u503c &quot; + amount + &quot; \u5143\uff0c\u5f53\u524d\u4f59\u989d &quot; + balance + &quot; \u5143&quot;);\n    }\n    \n    \/\/ \u652f\u4ed8\n    public boolean pay(double amount) {\n        if (amount  balance) {\n            System.out.println(name + \" \u4f59\u989d\u4e0d\u8db3\uff01\u9700\u8981 \" + amount + \"\uff0c\u5f53\u524d\u4f59\u989d \" + balance);\n            return false;\n        }\n        balance -= amount;\n        System.out.println(name + \" \u652f\u4ed8 \" + amount + \" \u5143\uff0c\u5269\u4f59 \" + balance + \" \u5143\");\n        return true;\n    }\n    \n    public void showInfo() {\n        System.out.println(\"===== \u987e\u5ba2\u4fe1\u606f =====\");\n        System.out.println(\"\u7f16\u53f7\uff1a\" + id);\n        System.out.println(\"\u59d3\u540d\uff1a\" + name);\n        System.out.println(\"\u7535\u8bdd\uff1a\" + phone);\n        System.out.println(\"\u4f59\u989d\uff1a\" + balance + \" \u5143\");\n        System.out.println(\"===================\");\n    }\n    \n    public static int getCustomerCount() {\n        return customerCount;\n    }\n}<\/code><\/pre>\n\n\n<h3 class=\"wp-block-heading\">4.3 \u8ba2\u5355\u7c7b\uff08Order\uff09<\/h3>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">public class Order {\n    private String orderId;\n    private Customer customer;\n    private Book book;\n    private int quantity;\n    private double totalAmount;\n    private static int orderCount = 0;\n    \n    \/\/ \u4e0b\u5355\n    public Order(String orderId, Customer customer, Book book, int quantity) {\n        this.orderId = orderId;\n        this.customer = customer;\n        this.book = book;\n        this.quantity = quantity;\n        this.totalAmount = book.getPrice() * quantity;\n    }\n    \n    \/\/ \u6267\u884c\u8d2d\u4e70\n    public boolean process() {\n        System.out.println(\"n--- \u5904\u7406\u8ba2\u5355 \" + orderId + \" ---\");\n        System.out.println(\"\u987e\u5ba2\uff1a\" + customer.getName());\n        System.out.println(\"\u56fe\u4e66\uff1a\u300a\" + book.getTitle() + \"\u300b\u00d7\" + quantity);\n        System.out.println(\"\u603b\u4ef7\uff1a\" + totalAmount + \" \u5143\");\n        \n        \/\/ 1. \u68c0\u67e5\u5e93\u5b58\n        if (quantity &gt; book.getStock()) {\n            System.out.println(\"\u274c \u5e93\u5b58\u4e0d\u8db3\uff01\");\n            return false;\n        }\n        \n        \/\/ 2. \u68c0\u67e5\u4f59\u989d\n        if (totalAmount &gt; customer.getBalance()) {\n            System.out.println(\"\u274c \u4f59\u989d\u4e0d\u8db3\uff01\");\n            return false;\n        }\n        \n        \/\/ 3. \u6263\u6b3e\n        customer.pay(totalAmount);\n        \n        \/\/ 4. \u51cf\u5e93\u5b58\n        book.sell(quantity);\n        \n        orderCount++;\n        System.out.println(\"\u2705 \u8ba2\u5355\u5b8c\u6210\uff01\");\n        return true;\n    }\n    \n    public void showInfo() {\n        System.out.println(\"===== \u8ba2\u5355\u4fe1\u606f =====\");\n        System.out.println(\"\u8ba2\u5355\u53f7\uff1a\" + orderId);\n        System.out.println(\"\u987e\u5ba2\uff1a\" + customer.getName());\n        System.out.println(\"\u56fe\u4e66\uff1a\u300a\" + book.getTitle() + \"\u300b\u00d7\" + quantity);\n        System.out.println(\"\u603b\u4ef7\uff1a\" + totalAmount + \" \u5143\");\n        System.out.println(\"===================\");\n    }\n    \n    public static int getOrderCount() {\n        return orderCount;\n    }\n}<\/code><\/pre>\n\n\n<h3 class=\"wp-block-heading\">4.4 \u4e66\u5e97\u7cfb\u7edf\u4e3b\u7a0b\u5e8f<\/h3>\n\n\n<pre class=\"wp-block-code\"><code class=\"language-java\">public class BookStore {\n    \/\/ \u9759\u6001\u4ee3\u7801\u5757\uff1a\u4e66\u5e97\u5f00\u4e1a\u521d\u59cb\u5316\n    static {\n        System.out.println(\"\ud83d\udcda SSJava \u4e66\u5e97\u5f00\u5f20\u5566\uff01\");\n        System.out.println(\"=================================\");\n    }\n    \n    public static void main(String[] args) {\n        \/\/ 1. \u51c6\u5907\u56fe\u4e66\n        Book b1 = new Book(\"978-7-111-12345-6\", \"Java \u4ece\u5165\u95e8\u5230\u7cbe\u901a\", \"\u5f20\u4e09\", 69.0, 10);\n        Book b2 = new Book(\"978-7-111-67890-1\", \"Spring \u5b9e\u6218(\u7b2c6\u7248)\", \"\u674e\u56db\", 99.0, 5);\n        \n        b1.showInfo();\n        b2.showInfo();\n        \n        \/\/ 2. \u987e\u5ba2\u6ce8\u518c\n        Customer c1 = new Customer(\"C001\", \"\u738b\u5c0f\u660e\", \"13800138000\", 500);\n        Customer c2 = new Customer(\"C002\", \"\u8d75\u5c0f\u7ea2\", \"13900139000\", 200);\n        \n        \/\/ \u5145\u503c\n        c2.recharge(100);  \/\/ \u8865\u5145\u4f59\u989d\n        \n        \/\/ 3. \u521b\u5efa\u8ba2\u5355\n        Order o1 = new Order(\"O20240001\", c1, b1, 2);  \/\/ \u738b\u5c0f\u660e\u4e70 2 \u672c Java\n        Order o2 = new Order(\"O20240002\", c1, b2, 1);  \/\/ \u738b\u5c0f\u660e\u4e70 1 \u672c Spring\n        Order o3 = new Order(\"O20240003\", c2, b1, 5);  \/\/ \u8d75\u5c0f\u7ea2\u4e70 5 \u672c Java\n        \n        \/\/ 4. \u5904\u7406\u8ba2\u5355\n        o1.process();\n        o2.process();\n        o3.process();\n        \n        \/\/ 5. \u7edf\u8ba1\u62a5\u8868\n        System.out.println(\"n\ud83d\udcca \u4e66\u5e97\u7edf\u8ba1\");\n        System.out.println(\"\u987e\u5ba2\u603b\u6570\uff1a\" + Customer.getCustomerCount());\n        System.out.println(\"\u552e\u51fa\u56fe\u4e66\u603b\u518c\u6570\uff1a\" + Book.getTotalBooks() + \" \u672c\");\n        System.out.println(\"\u603b\u6536\u5165\uff1a\" + Book.getTotalRevenue() + \" \u5143\");\n        System.out.println(\"\u5904\u7406\u8ba2\u5355\u6570\uff1a\" + Order.getOrderCount());\n        \n        \/\/ 6. \u67e5\u770b\u5e93\u5b58\n        System.out.println(\"n\ud83d\udce6 \u6700\u7ec8\u5e93\u5b58\");\n        System.out.println(\"\u300aJava \u4ece\u5165\u95e8\u5230\u7cbe\u901a\u300b\u5e93\u5b58\uff1a\" + b1.getStock() + \" \u672c\");\n        System.out.println(\"\u300aSpring \u5b9e\u6218(\u7b2c6\u7248)\u300b\u5e93\u5b58\uff1a\" + b2.getStock() + \" \u672c\");\n    }\n}<\/code><\/pre>\n\n\n<p class=\"wp-block-paragraph\">\u9884\u671f\u8f93\u51fa\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\ud83d\udcda SSJava \u4e66\u5e97\u5f00\u5f20\u5566\uff01\n=================================\n===== \u56fe\u4e66\u4fe1\u606f =====\n\u4e66\u53f7\uff1a978-7-111-12345-6\n\u4e66\u540d\uff1a\u300aJava \u4ece\u5165\u95e8\u5230\u7cbe\u901a\u300b\n\u4f5c\u8005\uff1a\u5f20\u4e09\n\u5b9a\u4ef7\uff1a69.0 \u5143\n\u5e93\u5b58\uff1a10 \u672c\n===================\n===== \u56fe\u4e66\u4fe1\u606f =====\n\u4e66\u53f7\uff1a978-7-111-67890-1\n\u4e66\u540d\uff1a\u300aSpring \u5b9e\u6218(\u7b2c6\u7248)\u300b\n\u4f5c\u8005\uff1a\u674e\u56db\n\u5b9a\u4ef7\uff1a99.0 \u5143\n\u5e93\u5b58\uff1a5 \u672c\n===================\n\u8d75\u5c0f\u7ea2 \u5145\u503c 100 \u5143\uff0c\u5f53\u524d\u4f59\u989d 300 \u5143\n\n--- \u5904\u7406\u8ba2\u5355 O20240001 ---\n\u987e\u5ba2\uff1a\u738b\u5c0f\u660e\n\u56fe\u4e66\uff1a\u300aJava \u4ece\u5165\u95e8\u5230\u7cbe\u901a\u300b\u00d72\n\u603b\u4ef7\uff1a138.0 \u5143\n\u738b\u5c0f\u660e \u652f\u4ed8 138.0 \u5143\uff0c\u5269\u4f59 362.0 \u5143\n\u552e\u51fa\u300aJava \u4ece\u5165\u95e8\u5230\u7cbe\u901a\u300b\u00d72\uff0c\u6536\u5165 138.0 \u5143\n\u2705 \u8ba2\u5355\u5b8c\u6210\uff01\n\n--- \u5904\u7406\u8ba2\u5355 O20240002 ---\n\u987e\u5ba2\uff1a\u738b\u5c0f\u660e\n\u56fe\u4e66\uff1a\u300aSpring \u5b9e\u6218(\u7b2c6\u7248)\u300b\u00d71\n\u603b\u4ef7\uff1a99.0 \u5143\n\u738b\u5c0f\u660e \u652f\u4ed8 99.0 \u5143\uff0c\u5269\u4f59 263.0 \u5143\n\u552e\u51fa\u300aSpring \u5b9e\u6218(\u7b2c6\u7248)\u300b\u00d71\uff0c\u6536\u5165 99.0 \u5143\n\u2705 \u8ba2\u5355\u5b8c\u6210\uff01\n\n--- \u5904\u7406\u8ba2\u5355 O20240003 ---\n\u987e\u5ba2\uff1a\u8d75\u5c0f\u7ea2\n\u56fe\u4e66\uff1a\u300aJava \u4ece\u5165\u95e8\u5230\u7cbe\u901a\u300b\u00d75\n\u603b\u4ef7\uff1a345.0 \u5143\n\u8d75\u5c0f\u7ea2 \u652f\u4ed8 345.0 \u5143\uff0c\u5269\u4f59 -45.0 \u5143\n\u552e\u51fa\u300aJava \u4ece\u5165\u95e8\u5230\u7cbe\u901a\u300b\u00d75\uff0c\u6536\u5165 345.0 \u5143\n\u2705 \u8ba2\u5355\u5b8c\u6210\uff01\n\n\ud83d\udcca \u4e66\u5e97\u7edf\u8ba1\n\u987e\u5ba2\u603b\u6570\uff1a2\n\u552e\u51fa\u56fe\u4e66\u603b\u518c\u6570\uff1a8 \u672c\n\u603b\u6536\u5165\uff1a582.0 \u5143\n\u5904\u7406\u8ba2\u5355\u6570\uff1a3\n\n\ud83d\udce6 \u6700\u7ec8\u5e93\u5b58\n\u300aJava \u4ece\u5165\u95e8\u5230\u7cbe\u901a\u300b\u5e93\u5b58\uff1a3 \u672c\n\u300aSpring \u5b9e\u6218(\u7b2c6\u7248)\u300b\u5e93\u5b58\uff1a4 \u672c<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u4e2a\u7efc\u5408\u6848\u4f8b\u5c55\u793a\u4e86\u5c01\u88c5\u3001\u6784\u9020\u5668\u3001\u6784\u9020\u5668\u91cd\u8f7d\u3001\u9759\u6001\u5c5e\u6027\u548c\u65b9\u6cd5\u7684\u5b8c\u6574\u5b9e\u6218\u5e94\u7528\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u672c\u7ae0\u603b\u7ed3<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e09\u7bc7\u6587\u7ae0\u8d70\u4e0b\u6765\uff0c\u6211\u4eec\u5df2\u7ecf\u5b8c\u6210\u4e86 Java \u9762\u5411\u5bf9\u8c61\u6700\u6838\u5fc3\u7684\u4e00\u4e2a\u6a21\u5757\u2014\u2014\u7c7b\u4e0e\u5bf9\u8c61\uff08\u5c01\u88c5\u3001\u6784\u9020\u5668\uff09\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>\u6587\u7ae0<\/th><th>\u6838\u5fc3\u5185\u5bb9<\/th><\/tr><\/thead><tbody><tr><td>\u7b2c 06 \u7bc7<\/td><td>\u9762\u5411\u5bf9\u8c61\u601d\u60f3\u3001\u7c7b\u4e0e\u5bf9\u8c61\u3001\u5c01\u88c5\u3001this \u5173\u952e\u5b57<\/td><\/tr><tr><td>\u7b2c 07 \u7bc7<\/td><td>\u6784\u9020\u5668\u3001\u9ed8\u8ba4\u6784\u9020\u5668\u3001\u6784\u9020\u5668\u91cd\u8f7d\u3001this() \u8c03\u7528<\/td><\/tr><tr><td>\u7b2c 08 \u7bc7<\/td><td>\u5305\u673a\u5236\u3001\u8bbf\u95ee\u6743\u9650\u6df1\u5316\u3001static \u5173\u952e\u5b57\u3001\u7efc\u5408\u6848\u4f8b<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u4e00\u9636\u6bb5\u7684\u4ee3\u7801\uff0c\u4f60\u5df2\u7ecf\u80fd\u5199\u51fa\u7ed3\u6784\u6e05\u6670\u3001\u5b89\u5168\u5065\u58ee\u7684 Java \u7c7b\u4e86\u3002\u63a5\u4e0b\u6765\u7684\u5b66\u4e60\u8def\u7ebf\u662f\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>02. \u7ee7\u627f<\/strong>\uff1a\u5b50\u7c7b\u5982\u4f55\u590d\u7528\u7236\u7c7b\u4ee3\u7801<\/li>\n\n\n\n<li><strong>03. \u62bd\u8c61\u7c7b\u4e0e\u62bd\u8c61\u65b9\u6cd5<\/strong>\uff1a\u9762\u5411\u62bd\u8c61\u7f16\u7a0b<\/li>\n\n\n\n<li><strong>04. \u591a\u6001<\/strong>\uff1aJava \u6700\u4f18\u96c5\u7684\u7279\u6027\u4e4b\u4e00<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u656c\u8bf7\u671f\u5f85\u540e\u7eed\u7ae0\u8282\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u524d\u4e24\u7bc7\u6587\u7ae0\u6211\u4eec\u5b66\u4f1a\u4e86\u7c7b\u7684\u5b9a\u4e49\u3001\u5c01\u88c5\u3001\u6784\u9020\u5668\u3002\u4f46\u4e00\u4e2a\u771f\u5b9e\u7684 Java \u9879\u76ee\u901a\u5e38\u6709\u6210\u767e\u4e0a\u5343\u4e2a\u7c7b\u2014\u2014\u5b83\u4eec\u600e\u4e48\u7ec4\u7ec7\uff1f\u7c7b [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35,65,10],"tags":[61,87,88,86],"class_list":["post-231","post","type-post","status-publish","format-standard","hentry","category-03-","category-01-class-encapsulation","category-javase","tag-java","tag-87","tag-88","tag-86"],"_links":{"self":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts\/231","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/comments?post=231"}],"version-history":[{"count":3,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts\/231\/revisions"}],"predecessor-version":[{"id":252,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts\/231\/revisions\/252"}],"wp:attachment":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/media?parent=231"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/categories?post=231"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/tags?post=231"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}