{"id":418,"date":"2026-03-07T09:21:48","date_gmt":"2026-03-07T00:21:48","guid":{"rendered":"https:\/\/i-third.org\/blog\/?p=418"},"modified":"2026-03-07T09:21:48","modified_gmt":"2026-03-07T00:21:48","slug":"%e3%80%90%e5%88%9d%e5%bf%83%e8%80%85%e5%bf%85%e8%a6%8b%e3%80%91java%e3%81%ae%e3%80%8c%e3%82%af%e3%83%a9%e3%82%b9%e3%80%8d%e3%82%92%e5%ae%8c%e5%85%a8%e3%83%9e%e3%82%b9%e3%82%bf%e3%83%bc%ef%bc%81","status":"publish","type":"post","link":"https:\/\/i-third.org\/blog\/?p=418","title":{"rendered":"\u3010\u521d\u5fc3\u8005\u5fc5\u898b\u3011Java\u306e\u300c\u30af\u30e9\u30b9\u300d\u3092\u5b8c\u5168\u30de\u30b9\u30bf\u30fc\uff01\u8a2d\u8a08\u56f3\u304b\u3089\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5316\u307e\u3067\u3001\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u306e\u7b2c\u4e00\u6b69\u3092\u4e38\u3054\u3068\u89e3\u8aac"},"content":{"rendered":"\n\n\n\n<p>\u300c\u30af\u30e9\u30b9\u3063\u3066\u5909\u6570\u3068\u30e1\u30bd\u30c3\u30c9\u3092\u307e\u3068\u3081\u305f\u3060\u3051\uff1f\u300d\u300c\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3068\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3063\u3066\u4f55\u304c\u9055\u3046\u306e\uff1f\u300d\u2014\u2014Java\u3092\u5b66\u3073\u59cb\u3081\u308b\u3068\u3001\u3053\u3046\u3044\u3063\u305f\u7591\u554f\u304c\u6b21\u3005\u3068\u6e67\u3044\u3066\u304d\u307e\u3059\u3088\u306d\u3002<\/p>\n\n\n\n<p>\u5b9f\u306f\u3001<strong>\u30af\u30e9\u30b9\u3053\u305d\u304cJava\u306e\u6838\u5fc3<\/strong>\u3067\u3059\u3002\u30af\u30e9\u30b9\u3092\u7406\u89e3\u3067\u304d\u308b\u3068\u3001\u300c\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u300d\u3068\u3044\u3046\u8003\u3048\u65b9\u304c\u4e00\u6c17\u306b\u30af\u30ea\u30a2\u306b\u306a\u308a\u3001\u3088\u308a\u5927\u898f\u6a21\u306a\u30d7\u30ed\u30b0\u30e9\u30e0\u304c\u66f8\u3051\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001IT\u7814\u4fee\u306e\u73fe\u5834\u3067\u521d\u5b66\u8005\u306b\u7e70\u308a\u8fd4\u3057\u4f1d\u3048\u3066\u304d\u305f\u8996\u70b9\u3092\u3082\u3068\u306b\u3001<strong>\u300c\u306a\u305c\u30af\u30e9\u30b9\u304c\u4fbf\u5229\u306a\u306e\u304b\u300d\u300cJava\u3067\u306e\u5b9a\u7fa9\u30fb\u5229\u7528\u65b9\u6cd5\u300d\u300c\u73fe\u5834\u3067\u5fc5\u305a\u62bc\u3055\u3048\u3066\u304a\u304d\u305f\u3044\u30dd\u30a4\u30f3\u30c8\u300d<\/strong>\u307e\u3067\u3001\u3066\u3044\u306d\u3044\u306b\u89e3\u8aac\u3057\u307e\u3059\u3002\u5177\u4f53\u7684\u306a\u30b3\u30fc\u30c9\u4f8b\u3082\u8c4a\u5bcc\u306b\u7528\u610f\u3057\u305f\u306e\u3067\u3001\u305c\u3072\u624b\u3092\u52d5\u304b\u3057\u306a\u304c\u3089\u8aad\u3093\u3067\u307f\u3066\u304f\u3060\u3055\u3044\uff01<\/p>\n\n\n<hr>\n\n\n<h2 class=\"wp-block-heading\" id=\"toc\">\u76ee\u6b21<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n  <li><a href=\"#section1\">\uff11\uff0e\u30af\u30e9\u30b9\u3063\u3066\u4f55\u304c\u4fbf\u5229\u306a\u306e\uff1f<\/a>\n    <ul>\n      <li><a href=\"#section1-1\">\u2460\u30c7\u30fc\u30bf\u3068\u30e1\u30bd\u30c3\u30c9\u3092\u300c\u3072\u3068\u307e\u3068\u3081\u300d\u306b\u3067\u304d\u308b<\/a><\/li>\n      <li><a href=\"#section1-2\">\u2461\u73fe\u5b9f\u4e16\u754c\u306e\u300c\u3082\u306e\u300d\u3092\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u8868\u73fe\u3067\u304d\u308b<\/a><\/li>\n      <li><a href=\"#section1-3\">\u2462\u300c\u8a2d\u8a08\u56f3\u300d\u3068\u3057\u3066\u4f55\u5ea6\u3067\u3082\u4f7f\u3044\u56de\u305b\u308b<\/a><\/li>\n    <\/ul>\n  <\/li>\n  <li><a href=\"#section2\">\uff12\uff0e\u30af\u30e9\u30b9\u3092\u5b9a\u7fa9\u3059\u308b\u3063\u3066\uff1f\u5229\u7528\u3059\u308b\u3063\u3066\uff1f<\/a>\n    <ul>\n      <li><a href=\"#section2-1\">\u2460\u30af\u30e9\u30b9\u306e\u5b9a\u7fa9\uff1a\u30d5\u30a3\u30fc\u30eb\u30c9\u3068\u30e1\u30bd\u30c3\u30c9\u3092\u307e\u3068\u3081\u308b\u57fa\u672c\u69cb\u6587<\/a><\/li>\n      <li><a href=\"#section2-2\">\u2461\u30af\u30e9\u30b9\u306e\u5229\u7528\uff1anew\u3067\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5316\u3057\u3066\u300c.\u300d\u3067\u30a2\u30af\u30bb\u30b9\u3059\u308b<\/a><\/li>\n      <li><a href=\"#section2-3\">\u2462\u30a2\u30af\u30bb\u30b9\u4fee\u98fe\u5b50\u3068\u30ab\u30d7\u30bb\u30eb\u5316\uff1a\u30b2\u30c3\u30bf\u30fc\u30fb\u30bb\u30c3\u30bf\u30fc\u3067\u5b89\u5168\u306b\u5b88\u308b<\/a><\/li>\n    <\/ul>\n  <\/li>\n  <li><a href=\"#section3\">\uff13\uff0e\u30af\u30e9\u30b9\u306b\u3064\u3044\u3066\u6574\u7406\u3057\u3066\u304a\u304d\u305f\u3044\u3053\u3068<\/a>\n    <ul>\n      <li><a href=\"#section3-1\">\u2460\u30af\u30e9\u30b9\u30fb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u30fb\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306e\u8a00\u8449\u306e\u9055\u3044<\/a><\/li>\n      <li><a href=\"#section3-2\">\u2461\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3068\u306f\uff1anew\u306e\u30bf\u30a4\u30df\u30f3\u30b0\u3067\u81ea\u52d5\u5b9f\u884c\u3055\u308c\u308b\u521d\u671f\u5316\u51e6\u7406<\/a><\/li>\n      <li><a href=\"#section3-3\">\u2462\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\u3068\u30ac\u30fc\u30d9\u30fc\u30b8\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306e\u57fa\u790e\u77e5\u8b58<\/a><\/li>\n    <\/ul>\n  <\/li>\n  <li><a href=\"#summary\">\u307e\u3068\u3081<\/a><\/li>\n<\/ul>\n\n\n<hr>\n\n\n<h2 class=\"wp-block-heading\" id=\"section1\">\uff11\uff0e\u30af\u30e9\u30b9\u3063\u3066\u4f55\u304c\u4fbf\u5229\u306a\u306e\uff1f<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"section1-1\">\u2460\u30c7\u30fc\u30bf\u3068\u30e1\u30bd\u30c3\u30c9\u3092\u300c\u3072\u3068\u307e\u3068\u3081\u300d\u306b\u3067\u304d\u308b<\/h3>\n\n\n\n<p>\u3053\u308c\u307e\u3067\u306b\u5b66\u3093\u3060\u300c\u5909\u6570\u300d\u306f1\u7a2e\u985e\u306e\u30c7\u30fc\u30bf\u3092\u5165\u308c\u308b\u7bb1\u3067\u3057\u305f\u3002\u3067\u3082\u73fe\u5b9f\u306e\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u306f\u3001<strong>\u8907\u6570\u306e\u30c7\u30fc\u30bf\u3092\u307e\u3068\u3081\u3066\u7ba1\u7406\u3057\u305f\u3044<\/strong>\u5834\u9762\u304c\u305f\u304f\u3055\u3093\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u305f\u3068\u3048\u3070\u300c\u793e\u54e1\u60c5\u5831\u300d\u3092\u7ba1\u7406\u3057\u305f\u3044\u3068\u304d\u3001\u5909\u6570\u3060\u3051\u3060\u3068\u3053\u3046\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre><code>\/\/ \u274c \u5909\u6570\u3060\u3051\u3067\u793e\u54e1\u60c5\u5831\u3092\u7ba1\u7406\u3057\u3088\u3046\u3068\u3059\u308b\u3068\u2026\nString employeeName1 = \"\u7530\u4e2d\";\nint employeeAge1 = 28;\nString employeeDept1 = \"\u958b\u767a\u90e8\";\n\nString employeeName2 = \"\u9234\u6728\";\nint employeeAge2 = 35;\nString employeeDept2 = \"\u55b6\u696d\u90e8\";\n\/\/ \u793e\u54e1\u304c\u5897\u3048\u308b\u305f\u3073\u306b\u5909\u6570\u304c\u7206\u767a\u7684\u306b\u5897\u3048\u308b\u2026<\/code><\/pre>\n\n\n\n<p>\u30af\u30e9\u30b9\u3092\u4f7f\u3046\u3068\u3001<strong>\u300c\u793e\u54e1\u300d\u3068\u3044\u3046\u3072\u3068\u307e\u3068\u307e\u308a\u306e\u578b<\/strong>\u3092\u81ea\u5206\u3067\u5b9a\u7fa9\u3067\u304d\u307e\u3059\u3002\u3053\u308c\u304c\u300c\u30e6\u30fc\u30b6\u30fc\u5b9a\u7fa9\u578b\u300d\u306e\u8003\u3048\u65b9\u3067\u3059\u3002<\/p>\n\n\n\n<pre><code>\/\/ \u2705 \u30af\u30e9\u30b9\u3092\u4f7f\u3046\u3068\u793e\u54e1\u60c5\u5831\u304c\u3072\u3068\u307e\u3068\u307e\u308a\u306b\nclass Employee {\n    String name;   \/\/ \u30d5\u30a3\u30fc\u30eb\u30c9\uff08\u5c5e\u6027\uff09\n    int age;\n    String dept;\n\n    void work() { \/\/ \u30e1\u30bd\u30c3\u30c9\uff08\u64cd\u4f5c\uff09\n        System.out.println(name + \"\u304c\u4ed5\u4e8b\u3092\u3057\u3066\u3044\u307e\u3059\");\n    }\n    double getSalary() {\n        return age * 1000.0; \/\/ \u4eee\u306e\u7d66\u4e0e\u8a08\u7b97\n    }\n}<\/code><\/pre>\n\n\n\n<p>\u30af\u30e9\u30b9\u306b\u306f<strong>\u300c\u30d5\u30a3\u30fc\u30eb\u30c9\uff08\u5c5e\u6027\uff09\u300d\u3068\u300c\u30e1\u30bd\u30c3\u30c9\uff08\u64cd\u4f5c\uff09\u300d\u306e\u4e21\u65b9\u3092\u5b9a\u7fa9\u3067\u304d\u308b<\/strong>\u306e\u304c\u30dd\u30a4\u30f3\u30c8\u3067\u3059\u3002\u30c7\u30fc\u30bf\u3068\u305d\u306e\u30c7\u30fc\u30bf\u306b\u95a2\u3059\u308b\u51e6\u7406\u304c\u30bb\u30c3\u30c8\u306b\u306a\u3063\u3066\u3044\u308b\u306e\u3067\u3001\u7ba1\u7406\u304c\u3068\u3066\u3082\u697d\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n<hr>\n\n\n<h3 class=\"wp-block-heading\" id=\"section1-2\">\u2461\u73fe\u5b9f\u4e16\u754c\u306e\u300c\u3082\u306e\u300d\u3092\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u8868\u73fe\u3067\u304d\u308b<\/h3>\n\n\n\n<p>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u306e\u8003\u3048\u65b9\u306e\u6839\u3063\u3053\u306f\u3001<strong>\u300c\u73fe\u5b9f\u4e16\u754c\u306b\u5b58\u5728\u3059\u308b\u3082\u306e\u3092\u305d\u306e\u307e\u307e\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u8868\u73fe\u3057\u3088\u3046\u300d<\/strong>\u3068\u3044\u3046\u30a2\u30a4\u30c7\u30a2\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u305f\u3068\u3048\u3070\u300c\u9280\u884c\u53e3\u5ea7\u300d\u3092\u8003\u3048\u3066\u307f\u307e\u3057\u3087\u3046\u3002\u73fe\u5b9f\u306e\u9280\u884c\u53e3\u5ea7\u306b\u306f\u300c\u6b8b\u9ad8\uff08\u5c5e\u6027\uff09\u300d\u304c\u3042\u308a\u3001\u300c\u5165\u91d1\u3059\u308b\u30fb\u51fa\u91d1\u3059\u308b\uff08\u64cd\u4f5c\uff09\u300d\u3068\u3044\u3046\u884c\u70ba\u304c\u3067\u304d\u307e\u3059\u3002\u3053\u308c\u3092\u305d\u306e\u307e\u307e\u30af\u30e9\u30b9\u3067\u8868\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre><code>class Account {\n    String owner;   \/\/ \u53e3\u5ea7\u540d\u7fa9\uff08\u5c5e\u6027\uff09\n    int balance;    \/\/ \u6b8b\u9ad8\uff08\u5c5e\u6027\uff09\n\n    void deposit(int amount) {   \/\/ \u5165\u91d1\u3059\u308b\uff08\u64cd\u4f5c\uff09\n        balance += amount;\n        System.out.println(amount + \"\u5186\u5165\u91d1\u3057\u307e\u3057\u305f\u3002\u6b8b\u9ad8\uff1a\" + balance + \"\u5186\");\n    }\n\n    void withdraw(int amount) {  \/\/ \u51fa\u91d1\u3059\u308b\uff08\u64cd\u4f5c\uff09\n        if (balance >= amount) {\n            balance -= amount;\n            System.out.println(amount + \"\u5186\u51fa\u91d1\u3057\u307e\u3057\u305f\u3002\u6b8b\u9ad8\uff1a\" + balance + \"\u5186\");\n        } else {\n            System.out.println(\"\u6b8b\u9ad8\u4e0d\u8db3\u3067\u3059\");\n        }\n    }\n}<\/code><\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306b\u3001\u73fe\u5b9f\u306e\u300c\u3082\u306e\u300d\u306e\u7279\u5fb4\uff08\u5c5e\u6027\uff09\u3068\u300c\u3067\u304d\u308b\u3053\u3068\u300d\uff08\u64cd\u4f5c\uff09\u3092\u305d\u306e\u307e\u307e\u30af\u30e9\u30b9\u306b\u843d\u3068\u3057\u8fbc\u3081\u307e\u3059\u3002\u3053\u308c\u304c<strong>\u300c\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u300d\u3068\u3044\u3046\u8a2d\u8a08\u601d\u60f3\u306e\u672c\u8cea<\/strong>\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u4ed6\u306b\u3082\u300c\u9867\u5ba2\u30af\u30e9\u30b9\u300d\u300c\u5546\u54c1\u30af\u30e9\u30b9\u300d\u300c\u6ce8\u6587\u30af\u30e9\u30b9\u300d\u306a\u3069\u3001\u696d\u52d9\u30b7\u30b9\u30c6\u30e0\u306e\u4e3b\u8981\u306a\u6982\u5ff5\u304c\u305d\u306e\u307e\u307e\u30af\u30e9\u30b9\u3068\u3057\u3066\u8868\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n<hr>\n\n\n<h3 class=\"wp-block-heading\" id=\"section1-3\">\u2462\u300c\u8a2d\u8a08\u56f3\u300d\u3068\u3057\u3066\u4f55\u5ea6\u3067\u3082\u4f7f\u3044\u56de\u305b\u308b<\/h3>\n\n\n\n<p>\u30af\u30e9\u30b9\u306f<strong>\u300c\u8a2d\u8a08\u56f3\uff08\u3072\u306a\u5f62\uff09\u300d<\/strong>\u3067\u3059\u3002\u8a2d\u8a08\u56f3\u305d\u306e\u3082\u306e\u306f\u30e1\u30e2\u30ea\u3092\u4f7f\u3044\u307e\u305b\u3093\u304c\u3001\u8a2d\u8a08\u56f3\u3092\u3082\u3068\u306b\u300c\u5b9f\u4f53\uff08\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\uff09\u300d\u3092\u4f55\u500b\u3067\u3082\u4f5c\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u5bb6\u306e\u8a2d\u8a08\u56f3\u306b\u4f8b\u3048\u308b\u3068\u2014\u2014\u540c\u3058\u8a2d\u8a08\u56f3\u304b\u3089\u4f55\u68df\u3067\u3082\u5bb6\u3092\u5efa\u3066\u3089\u308c\u307e\u3059\u3088\u306d\u3002\u305d\u308c\u305e\u308c\u306e\u5bb6\u306b\u306f\u9055\u3046\u4eba\u304c\u4f4f\u3093\u3067\u3044\u3066\u3001\u9055\u3046\u5bb6\u5177\u304c\u7f6e\u3044\u3066\u3042\u308b\u3002\u30af\u30e9\u30b9\u3068\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306e\u95a2\u4fc2\u3082\u307e\u3063\u305f\u304f\u540c\u3058\u3067\u3059\u3002<\/p>\n\n\n\n<pre><code>\/\/ Account\u30af\u30e9\u30b9\uff08\u8a2d\u8a08\u56f3\uff09\u304b\u3089\u8907\u6570\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u751f\u6210\nAccount account1 = new Account();   \/\/ \u7530\u4e2d\u3055\u3093\u306e\u53e3\u5ea7\naccount1.owner = \"\u7530\u4e2d\";\naccount1.balance = 50000;\n\nAccount account2 = new Account();   \/\/ \u9234\u6728\u3055\u3093\u306e\u53e3\u5ea7\naccount2.owner = \"\u9234\u6728\";\naccount2.balance = 120000;\n\n\/\/ \u305d\u308c\u305e\u308c\u72ec\u7acb\u3057\u305f\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3068\u3057\u3066\u5b58\u5728\u3059\u308b\naccount1.deposit(10000);   \/\/ \u7530\u4e2d\u3055\u3093\u306e\u6b8b\u9ad8\u304c\u5909\u308f\u308b\naccount2.withdraw(5000);   \/\/ \u9234\u6728\u3055\u3093\u306e\u6b8b\u9ad8\u304c\u5909\u308f\u308b\uff08\u7530\u4e2d\u3055\u3093\u306b\u306f\u7121\u95a2\u4fc2\uff09<\/code><\/pre>\n\n\n\n<p>1\u3064\u306e\u30af\u30e9\u30b9\u5b9a\u7fa9\u304b\u3089\u3001\u4f55\u500b\u3067\u3082\u72ec\u7acb\u3057\u305f\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u4f5c\u308c\u308b\u3002\u3053\u308c\u304c\u30af\u30e9\u30b9\u306e\u6700\u5927\u306e\u300c\u4f7f\u3044\u56de\u3057\u300d\u306e\u30e1\u30ea\u30c3\u30c8\u3067\u3059\u3002<\/p>\n\n\n<hr>\n\n\n<h2 class=\"wp-block-heading\" id=\"section2\">\uff12\uff0e\u30af\u30e9\u30b9\u3092\u5b9a\u7fa9\u3059\u308b\u3063\u3066\uff1f\u5229\u7528\u3059\u308b\u3063\u3066\uff1f<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"section2-1\">\u2460\u30af\u30e9\u30b9\u306e\u5b9a\u7fa9\uff1a\u30d5\u30a3\u30fc\u30eb\u30c9\u3068\u30e1\u30bd\u30c3\u30c9\u3092\u307e\u3068\u3081\u308b\u57fa\u672c\u69cb\u6587<\/h3>\n\n\n\n<p>Java\u3067\u30af\u30e9\u30b9\u3092\u5b9a\u7fa9\u3059\u308b\u57fa\u672c\u69cb\u6587\u306f\u3053\u3046\u3067\u3059\u3002<\/p>\n\n\n\n<pre><code>class \u30af\u30e9\u30b9\u540d {\n    \/\/ \u30d5\u30a3\u30fc\u30eb\u30c9\uff08\u5c5e\u6027\uff1a\u30c7\u30fc\u30bf\u3092\u4fdd\u6301\u3059\u308b\u5909\u6570\uff09\n    \u30c7\u30fc\u30bf\u578b \u30d5\u30a3\u30fc\u30eb\u30c9\u540d;\n\n    \/\/ \u30e1\u30bd\u30c3\u30c9\uff08\u64cd\u4f5c\uff1a\u51e6\u7406\u3092\u5b9a\u7fa9\u3059\u308b\uff09\n    \u623b\u308a\u5024\u306e\u578b \u30e1\u30bd\u30c3\u30c9\u540d(\u5f15\u6570) {\n        \/\/ \u51e6\u7406\u5185\u5bb9\n    }\n}<\/code><\/pre>\n\n\n\n<p>\u5177\u4f53\u4f8b\u3068\u3057\u3066\u300c\u70b9\uff08Point\uff09\u30af\u30e9\u30b9\u300d\u3092\u4f5c\u3063\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<pre><code>class Point {\n    \/\/ \u30d5\u30a3\u30fc\u30eb\u30c9\uff08\u5ea7\u6a19\u306e\u5c5e\u6027\uff09\n    int x;\n    int y;\n\n    \/\/ \u30e1\u30bd\u30c3\u30c9\uff082\u70b9\u9593\u306e\u8ddd\u96e2\u3092\u8fd4\u3059\u64cd\u4f5c\uff09\n    double distanceTo(Point other) {\n        int dx = this.x - other.x;\n        int dy = this.y - other.y;\n        return Math.sqrt(dx * dx + dy * dy);\n    }\n\n    \/\/ \u30e1\u30bd\u30c3\u30c9\uff08\u5ea7\u6a19\u3092\u8868\u793a\u3059\u308b\u64cd\u4f5c\uff09\n    void display() {\n        System.out.println(\"(\" + x + \", \" + y + \")\");\n    }\n}<\/code><\/pre>\n\n\n\n<p>\u3053\u3053\u3067\u767b\u5834\u3057\u305f <code>this<\/code> \u30ad\u30fc\u30ef\u30fc\u30c9\u306f<strong>\u300c\u3053\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u81ea\u8eab\u300d<\/strong>\u3092\u6307\u3057\u307e\u3059\u3002<code>this.x<\/code> \u306f\u300c\u3053\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306e\u30d5\u30a3\u30fc\u30eb\u30c9 x\u300d\u3068\u3044\u3046\u610f\u5473\u3067\u3059\u3002\u5f15\u6570\u540d\u3068\u30d5\u30a3\u30fc\u30eb\u30c9\u540d\u304c\u540c\u3058\u306b\u306a\u308b\u3068\u304d\u306a\u3069\u306b\u7279\u306b\u6d3b\u8e8d\u3057\u307e\u3059\u3002<\/p>\n\n\n<hr>\n\n\n<h3 class=\"wp-block-heading\" id=\"section2-2\">\u2461\u30af\u30e9\u30b9\u306e\u5229\u7528\uff1anew\u3067\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5316\u3057\u3066\u300c.\u300d\u3067\u30a2\u30af\u30bb\u30b9\u3059\u308b<\/h3>\n\n\n\n<p>\u30af\u30e9\u30b9\uff08\u8a2d\u8a08\u56f3\uff09\u3092\u5b9a\u7fa9\u3057\u305f\u3060\u3051\u3067\u306f\u4f55\u3082\u8d77\u304d\u307e\u305b\u3093\u3002<strong><code>new<\/code> \u6f14\u7b97\u5b50\u3092\u4f7f\u3063\u3066\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u751f\u6210\u3057\u3066\u521d\u3081\u3066\u3001\u30e1\u30e2\u30ea\u4e0a\u306b\u5b9f\u4f53\u304c\u4f5c\u3089\u308c\u307e\u3059<\/strong>\u3002\u3053\u308c\u3092\u300c\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5316\u300d\u3068\u3044\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<pre><code>\/\/ \u30af\u30e9\u30b9\u540d \u5909\u6570\u540d = new \u30af\u30e9\u30b9\u540d();\nPoint p1 = new Point();\n\n\/\/ \u30d5\u30a3\u30fc\u30eb\u30c9\u3078\u306e\u30a2\u30af\u30bb\u30b9\u306f\u300c.\uff08\u30c9\u30c3\u30c8\uff09\u300d\u3092\u4f7f\u3046\np1.x = 3;\np1.y = 4;\n\n\/\/ \u30e1\u30bd\u30c3\u30c9\u306e\u547c\u3073\u51fa\u3057\u3082\u300c.\uff08\u30c9\u30c3\u30c8\uff09\u300d\u3092\u4f7f\u3046\np1.display();   \/\/ \u2192 (3, 4)\n\n\/\/ \u5225\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3082\u751f\u6210\u3057\u3066\u307f\u308b\nPoint p2 = new Point();\np2.x = 0;\np2.y = 0;\n\n\/\/ p1\u304b\u3089p2\u3078\u306e\u8ddd\u96e2\u3092\u8a08\u7b97\ndouble dist = p1.distanceTo(p2);\nSystem.out.println(\"\u8ddd\u96e2\uff1a\" + dist);   \/\/ \u2192 \u8ddd\u96e2\uff1a5.0<\/code><\/pre>\n\n\n\n<p><code>new<\/code> \u306e\u3042\u3068\u306b\u547c\u3073\u51fa\u3057\u3066\u3044\u308b <code>Point()<\/code> \u306f<strong>\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf<\/strong>\u3067\u3059\uff08\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u3067\u8a73\u3057\u304f\u89e3\u8aac\u3057\u307e\u3059\uff09\u3002<\/p>\n\n\n\n<p>\u307e\u305f\u3001\u4ed6\u306e\u30af\u30e9\u30b9\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u547c\u3073\u51fa\u3059\u5834\u5408\u306f\u3001\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u751f\u6210\u3057\u305f\u4e0a\u3067 <code>\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5909\u6570.\u30e1\u30bd\u30c3\u30c9\u540d()<\/code> \u306e\u5f62\u3067\u30a2\u30af\u30bb\u30b9\u3057\u307e\u3059\u3002\u3053\u308c\u304c<strong>\u300c\u30af\u30e9\u30b9\u3092\u5229\u7528\u3059\u308b\u300d<\/strong>\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n<hr>\n\n\n<h3 class=\"wp-block-heading\" id=\"section2-3\">\u2462\u30a2\u30af\u30bb\u30b9\u4fee\u98fe\u5b50\u3068\u30ab\u30d7\u30bb\u30eb\u5316\uff1a\u30b2\u30c3\u30bf\u30fc\u30fb\u30bb\u30c3\u30bf\u30fc\u3067\u5b89\u5168\u306b\u5b88\u308b<\/h3>\n\n\n\n<p>\u30af\u30e9\u30b9\u306e\u30d5\u30a3\u30fc\u30eb\u30c9\u3092\u5916\u90e8\u304b\u3089\u76f4\u63a5\u66f8\u304d\u63db\u3048\u3089\u308c\u308b\u3068\u3001<strong>\u610f\u56f3\u3057\u306a\u3044\u5024\u304c\u5165\u308a\u8fbc\u3093\u3067\u30d0\u30b0\u306e\u539f\u56e0<\/strong>\u306b\u306a\u308a\u307e\u3059\u3002\u3053\u308c\u3092\u9632\u3050\u306e\u304c<strong>\u30ab\u30d7\u30bb\u30eb\u5316\uff08\u60c5\u5831\u96a0\u853d\uff09<\/strong>\u3068\u3044\u3046\u8003\u3048\u65b9\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u30a2\u30af\u30bb\u30b9\u4fee\u98fe\u5b50\u3092\u4f7f\u3063\u3066\u3001\u30d5\u30a3\u30fc\u30eb\u30c9\u306e\u516c\u958b\u7bc4\u56f2\u3092\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\">\n<table>\n  <thead>\n    <tr>\n      <th>\u4fee\u98fe\u5b50<\/th>\n      <th>\u30a2\u30af\u30bb\u30b9\u7bc4\u56f2<\/th>\n      <th>\u4f7f\u3044\u3069\u3053\u308d<\/th>\n    <\/tr>\n  <\/thead>\n  <tbody>\n    <tr><td><code>public<\/code><\/td><td>\u3069\u3053\u304b\u3089\u3067\u3082\u30a2\u30af\u30bb\u30b9\u53ef\u80fd<\/td><td>\u5916\u90e8\u306b\u516c\u958b\u3057\u305f\u3044\u30e1\u30bd\u30c3\u30c9\u306b\u4f7f\u3046<\/td><\/tr>\n    <tr><td><code>private<\/code><\/td><td>\u540c\u3058\u30af\u30e9\u30b9\u5185\u304b\u3089\u306e\u307f\u30a2\u30af\u30bb\u30b9\u53ef\u80fd<\/td><td>\u76f4\u63a5\u89e6\u3089\u308c\u305f\u304f\u306a\u3044\u30d5\u30a3\u30fc\u30eb\u30c9\u306b\u4f7f\u3046<\/td><\/tr>\n    <tr><td>\uff08\u306a\u3057\uff09<\/td><td>\u540c\u3058\u30d1\u30c3\u30b1\u30fc\u30b8\u5185\u304b\u3089\u30a2\u30af\u30bb\u30b9\u53ef\u80fd<\/td><td>\u30d1\u30c3\u30b1\u30fc\u30b8\u5185\u3067\u306e\u5171\u6709\u306b\u4f7f\u3046<\/td><\/tr>\n  <\/tbody>\n<\/table>\n<\/figure>\n\n\n\n<p>\u30ab\u30d7\u30bb\u30eb\u5316\u306e\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3\u306f<strong>\u300c\u30d5\u30a3\u30fc\u30eb\u30c9\u306fprivate\u3001\u30a2\u30af\u30bb\u30b9\u306fpublic\u306a\u30b2\u30c3\u30bf\u30fc\u30fb\u30bb\u30c3\u30bf\u30fc\u7d4c\u7531\u300d<\/strong>\u3067\u3059\u3002<\/p>\n\n\n\n<pre><code>class Account {\n    private String owner;   \/\/ \u2190 private\u306b\u3057\u3066\u5916\u90e8\u304b\u3089\u76f4\u63a5\u89e6\u308c\u306a\u3044\u3088\u3046\u306b\u3059\u308b\n    private int balance;\n\n    \/\/ \u30b2\u30c3\u30bf\u30fc\uff08\u5024\u3092\u53d6\u5f97\u3059\u308b\u30e1\u30bd\u30c3\u30c9\uff09\n    public String getOwner() {\n        return owner;\n    }\n\n    public int getBalance() {\n        return balance;\n    }\n\n    \/\/ \u30bb\u30c3\u30bf\u30fc\uff08\u5024\u3092\u8a2d\u5b9a\u3059\u308b\u30e1\u30bd\u30c3\u30c9\uff09\n    public void setOwner(String owner) {\n        this.owner = owner;\n    }\n\n    public void setBalance(int balance) {\n        if (balance >= 0) {           \/\/ \u2190 \u4e0d\u6b63\u306a\u5024\u3092\u5f3e\u304f\u30c1\u30a7\u30c3\u30af\u3092\u5165\u308c\u3089\u308c\u308b\uff01\n            this.balance = balance;\n        } else {\n            System.out.println(\"\u6b8b\u9ad8\u306b\u8ca0\u306e\u5024\u306f\u8a2d\u5b9a\u3067\u304d\u307e\u305b\u3093\");\n        }\n    }\n}<\/code><\/pre>\n\n\n\n<pre><code>\/\/ \u5229\u7528\u3059\u308b\u5074\nAccount act = new Account();\nact.setOwner(\"\u7530\u4e2d\");\nact.setBalance(50000);\n\n\/\/ act.balance = -9999;  \u2190 \u274c private\u306a\u306e\u3067\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc\uff01\u76f4\u63a5\u89e6\u308c\u306a\u3044\nSystem.out.println(act.getBalance());   \/\/ \u2705 \u30b2\u30c3\u30bf\u30fc\u7d4c\u7531\u3067\u30a2\u30af\u30bb\u30b9 \u2192 50000<\/code><\/pre>\n\n\n\n<p>\u30bb\u30c3\u30bf\u30fc\u306e\u4e2d\u306b\u300c\u6b8b\u9ad8\u304c0\u4ee5\u4e0a\u304b\u3069\u3046\u304b\u300d\u306e\u30c1\u30a7\u30c3\u30af\u3092\u5165\u308c\u3089\u308c\u3066\u3044\u308b\u306e\u304c\u30dd\u30a4\u30f3\u30c8\u3067\u3059\u3002<strong>\u30c7\u30fc\u30bf\u306e\u6574\u5408\u6027\u3092\u30af\u30e9\u30b9\u81ea\u8eab\u304c\u5b88\u308b<\/strong>\u2014\u2014\u3053\u308c\u304c\u30ab\u30d7\u30bb\u30eb\u5316\u306e\u771f\u306e\u4fa1\u5024\u3067\u3059\u3002<\/p>\n\n\n<hr>\n\n\n<h2 class=\"wp-block-heading\" id=\"section3\">\uff13\uff0e\u30af\u30e9\u30b9\u306b\u3064\u3044\u3066\u6574\u7406\u3057\u3066\u304a\u304d\u305f\u3044\u3053\u3068<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"section3-1\">\u2460\u30af\u30e9\u30b9\u30fb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u30fb\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306e\u8a00\u8449\u306e\u9055\u3044<\/h3>\n\n\n\n<p>\u300c\u30af\u30e9\u30b9\u300d\u300c\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u300d\u300c\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u300d\u2014\u2014\u4f3c\u305f\u3088\u3046\u306a\u8a00\u8449\u304c\u4e26\u3093\u3067\u3044\u3066\u6df7\u4e71\u3057\u3084\u3059\u3044\u306e\u3067\u3001\u3057\u3063\u304b\u308a\u6574\u7406\u3057\u3066\u304a\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\">\n<table>\n  <thead>\n    <tr>\n      <th>\u7528\u8a9e<\/th>\n      <th>\u610f\u5473<\/th>\n      <th>\u305f\u3068\u3048\u8a71<\/th>\n    <\/tr>\n  <\/thead>\n  <tbody>\n    <tr>\n      <td><strong>\u30af\u30e9\u30b9<\/strong><\/td>\n      <td>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u3072\u306a\u5f62\uff08\u8a2d\u8a08\u56f3\uff09\u3002\u5024\u3092\u6301\u305f\u306a\u3044<\/td>\n      <td>\u5bb6\u306e\u8a2d\u8a08\u56f3<\/td>\n    <\/tr>\n    <tr>\n      <td><strong>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8<\/strong><\/td>\n      <td>\u300c\u3082\u306e\u300d\u3092\u62bd\u8c61\u5316\u3057\u3066\u8868\u73fe\u3057\u305f\u6982\u5ff5\u3002\u5e83\u3044\u610f\u5473\u3067\u4f7f\u308f\u308c\u308b<\/td>\n      <td>\u300c\u5bb6\u300d\u3068\u3044\u3046\u6982\u5ff5<\/td>\n    <\/tr>\n    <tr>\n      <td><strong>\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9<\/strong><\/td>\n      <td>\u30af\u30e9\u30b9\u3092\u3082\u3068\u306b\u30e1\u30e2\u30ea\u4e0a\u306b\u751f\u6210\u3055\u308c\u305f\u5177\u4f53\u7684\u306a\u5b9f\u4f53\u3002\u5177\u4f53\u7684\u306a\u5024\u3092\u6301\u3064<\/td>\n      <td>\u8a2d\u8a08\u56f3\u304b\u3089\u5b9f\u969b\u306b\u5efa\u3066\u305f1\u68df\u306e\u5bb6<\/td>\n    <\/tr>\n  <\/tbody>\n<\/table>\n\n\n\n<p>\u6280\u8853\u7684\u306b\u6b63\u78ba\u306b\u8a00\u3046\u3068\u3001<strong>\u30af\u30e9\u30b9\u306e\u5c5e\u6027\uff08\u30d5\u30a3\u30fc\u30eb\u30c9\uff09\u306f\u5024\u3092\u6301\u3061\u307e\u305b\u3093<\/strong>\u3002\u5024\u3092\u6301\u3064\u306e\u306f\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3067\u3059\u3002\u8a2d\u8a08\u56f3\u306b\u300c\u5bdd\u5ba4\u306e\u5e83\u3055\uff1a8\u7573\u300d\u3068\u66f8\u3044\u3066\u3042\u3063\u3066\u3082\u3001\u8a2d\u8a08\u56f3\u306b\u300c\u5b9f\u969b\u306e8\u7573\u306e\u7a7a\u9593\u300d\u306f\u306a\u3044\u3067\u3059\u3088\u306d\u3002<\/p>\n\n\n\n<pre><code>\/\/ Employee\u30af\u30e9\u30b9\uff08\u8a2d\u8a08\u56f3\uff09\u306f\u5024\u3092\u6301\u305f\u306a\u3044\n\/\/ \u2193\nEmployee emp1 = new Employee();   \/\/ \u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u751f\u6210\nemp1.name = \"\u7530\u4e2d\";    \/\/ \u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u304c\u521d\u3081\u3066\u5024\u3092\u6301\u3064\nemp1.age = 28;\n\nEmployee emp2 = new Employee();   \/\/ \u5225\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u751f\u6210\nemp2.name = \"\u9234\u6728\";   \/\/ emp1\u3068\u306f\u72ec\u7acb\u3057\u305f\u5024\nemp2.age = 35;\n\n\/\/ emp1\u3092\u5909\u3048\u3066\u3082emp2\u306f\u5909\u308f\u3089\u306a\u3044\uff08\u5225\u3005\u306e\u5b9f\u4f53\uff09\nemp1.age = 29;\nSystem.out.println(emp2.age);   \/\/ \u2192 35\uff08\u5909\u308f\u3063\u3066\u3044\u306a\u3044\uff09<\/code><\/pre>\n\n\n\n<p>\u306a\u304a\u3001\u300c\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3068\u547c\u3076\u300d\u306e\u306f\u8aa4\u308a\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u304c\u3001\u300c\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3068\u547c\u3076\u300d\u306e\u306f\u6b63\u78ba\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u3053\u306e\u5fae\u5999\u306a\u30cb\u30e5\u30a2\u30f3\u30b9\u3082\u982d\u306b\u5165\u308c\u3066\u304a\u304f\u3068\u3001\u6280\u8853\u7684\u306a\u4f1a\u8a71\u3067\u6df7\u4e71\u3057\u306a\u304f\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n<hr>\n\n\n<h3 class=\"wp-block-heading\" id=\"section3-2\">\u2461\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3068\u306f\uff1anew\u306e\u30bf\u30a4\u30df\u30f3\u30b0\u3067\u81ea\u52d5\u5b9f\u884c\u3055\u308c\u308b\u521d\u671f\u5316\u51e6\u7406<\/h3>\n\n\n\n<p><strong>\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf<\/strong>\u306f\u3001<code>new<\/code> \u3067\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u751f\u6210\u3057\u305f\u3068\u304d\u306b<strong>\u81ea\u52d5\u7684\u306b\u547c\u3070\u308c\u308b\u7279\u5225\u306a\u30e1\u30bd\u30c3\u30c9<\/strong>\u3067\u3059\u3002\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306e\u521d\u671f\u5316\uff08\u521d\u671f\u5024\u306e\u8a2d\u5b9a\u306a\u3069\uff09\u306b\u4f7f\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u306e\u7279\u5fb4\u306f\u6b21\u306e3\u3064\u3067\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n  <li>\u2705 <strong>\u30af\u30e9\u30b9\u540d\u3068\u540c\u3058\u540d\u524d<\/strong>\u306b\u3059\u308b<\/li>\n  <li>\u2705 <strong>\u623b\u308a\u5024\u306e\u578b\u3092\u66f8\u304b\u306a\u3044<\/strong>\uff08void\u3082\u66f8\u304b\u306a\u3044\uff09<\/li>\n  <li>\u2705 <code>new<\/code> \u306e\u30bf\u30a4\u30df\u30f3\u30b0\u3067<strong>\u81ea\u52d5\u7684\u306b\u547c\u3073\u51fa\u3055\u308c\u308b<\/strong><\/li>\n<\/ul>\n\n\n\n<pre><code>class Account {\n    private String owner;\n    private int balance;\n\n    \/\/ \u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\uff08\u30af\u30e9\u30b9\u540d\u3068\u540c\u3058\u540d\u524d\u3001\u623b\u308a\u5024\u306a\u3057\uff09\n    public Account(String owner, int initialBalance) {\n        this.owner = owner;\n        this.balance = initialBalance;\n        System.out.println(owner + \"\u306e\u53e3\u5ea7\u3092\u958b\u8a2d\u3057\u307e\u3057\u305f\uff08\u6b8b\u9ad8\uff1a\" + initialBalance + \"\u5186\uff09\");\n    }\n}\n\n\/\/ \u5229\u7528\u3059\u308b\u5074\nAccount act = new Account(\"\u7530\u4e2d\", 50000);\n\/\/ \u2192 \u7530\u4e2d\u306e\u53e3\u5ea7\u3092\u958b\u8a2d\u3057\u307e\u3057\u305f\uff08\u6b8b\u9ad8\uff1a50000\u5186\uff09\n\/\/ \u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u751f\u6210\u3068\u540c\u6642\u306b\u521d\u671f\u5024\u304c\u8a2d\u5b9a\u3055\u308c\u308b\uff01<\/code><\/pre>\n\n\n\n<p>\u3082\u3057\u30af\u30e9\u30b9\u306b\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3092\u5b9a\u7fa9\u3057\u306a\u304b\u3063\u305f\u5834\u5408\u3001Java\u304c\u81ea\u52d5\u7684\u306b<strong>\u5f15\u6570\u306a\u3057\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf<\/strong>\u3092\u751f\u6210\u3057\u3066\u304f\u308c\u307e\u3059\u3002\u305f\u3060\u3057\u3001\u81ea\u5206\u3067\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3092\u5b9a\u7fa9\u3057\u305f\u5834\u5408\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u306f\u81ea\u52d5\u751f\u6210\u3055\u308c\u306a\u3044\u306e\u3067\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<pre><code>\/\/ \u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3092\u5b9a\u7fa9\u3057\u306a\u304b\u3063\u305f\u5834\u5408\u306f\u3001\u3053\u308c\u304c\u81ea\u52d5\u751f\u6210\u3055\u308c\u308b\n\/\/ public Account() { }  \u2190 \u30c7\u30d5\u30a9\u30eb\u30c8\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\n\n\/\/ \u305f\u3060\u3057\u3001\u5f15\u6570\u3042\u308a\u306e\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3092\u5b9a\u7fa9\u3059\u308b\u3068\u2026\n\/\/ public Account(String owner, int balance) { ... }\n\/\/ \u2191 \u3053\u308c\u3092\u5b9a\u7fa9\u3057\u305f\u5834\u5408\u3001\u4e0b\u306e\u547c\u3073\u51fa\u3057\u306f\u30a8\u30e9\u30fc\u306b\u306a\u308b\nAccount act = new Account();   \/\/ \u274c \u5f15\u6570\u306a\u3057\u306e\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u304c\u306a\u3044\uff01<\/code><\/pre>\n\n\n<hr>\n\n\n<h3 class=\"wp-block-heading\" id=\"section3-3\">\u2462\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\u3068\u30ac\u30fc\u30d9\u30fc\u30b8\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306e\u57fa\u790e\u77e5\u8b58<\/h3>\n\n\n\n<p><strong>\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9<\/strong>\u3068\u306f\u3001<strong>\u540c\u3058\u30af\u30e9\u30b9\u5185\u306b\u540c\u3058\u540d\u524d\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u8907\u6570\u5b9a\u7fa9\u3059\u308b\u3053\u3068<\/strong>\u3067\u3059\u3002\u5f15\u6570\u306e\u6570\u3084\u578b\u304c\u7570\u306a\u308c\u3070\u3001\u540c\u3058\u30e1\u30bd\u30c3\u30c9\u540d\u3092\u4f7f\u3048\u307e\u3059\u3002<\/p>\n\n\n\n<pre><code>class Calculator {\n    \/\/ \u5f15\u6570\u304c2\u3064\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\n    static int add(int a, int b) {\n        return a + b;\n    }\n\n    \/\/ \u5f15\u6570\u304c3\u3064\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\uff08\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\uff09\n    static int add(int a, int b, int c) {\n        return a + b + c;\n    }\n\n    \/\/ \u5f15\u6570\u306e\u578b\u304cdouble\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\uff08\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\uff09\n    static double add(double a, double b) {\n        return a + b;\n    }\n}\n\n\/\/ \u547c\u3073\u51fa\u3057\u5074\uff1a\u540c\u3058\u540d\u524dadd\u3067\u3001\u5f15\u6570\u306b\u3088\u3063\u3066\u81ea\u52d5\u7684\u306b\u9069\u5207\u306a\u30e1\u30bd\u30c3\u30c9\u304c\u9078\u3070\u308c\u308b\nSystem.out.println(Calculator.add(1, 2));         \/\/ \u2192 3\uff082\u5f15\u6570int\u7248\uff09\nSystem.out.println(Calculator.add(1, 2, 3));      \/\/ \u2192 6\uff083\u5f15\u6570int\u7248\uff09\nSystem.out.println(Calculator.add(1.5, 2.5));     \/\/ \u2192 4.0\uff08double\u7248\uff09<\/code><\/pre>\n\n\n\n<p>\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u3082\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\u3067\u304d\u307e\u3059\u3002\u521d\u671f\u5316\u30d1\u30bf\u30fc\u30f3\u3092\u8907\u6570\u7528\u610f\u3057\u3066\u304a\u304f\u3053\u3068\u3067\u3001\u5229\u7528\u3059\u308b\u5074\u306e\u67d4\u8edf\u6027\u304c\u4e0a\u304c\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u6b21\u306b<strong>\u30ac\u30fc\u30d9\u30fc\u30b8\u30b3\u30ec\u30af\u30b7\u30e7\u30f3<\/strong>\u306b\u3064\u3044\u3066\u3002Java\u3067\u306f\u3001<strong>\u4e0d\u8981\u306b\u306a\u3063\u305f\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306fJVM\uff08Java\u4eee\u60f3\u30de\u30b7\u30f3\uff09\u304c\u81ea\u52d5\u7684\u306b\u30e1\u30e2\u30ea\u304b\u3089\u89e3\u653e<\/strong>\u3057\u3066\u304f\u308c\u307e\u3059\u3002\u3053\u308c\u304c\u30ac\u30fc\u30d9\u30fc\u30b8\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u3067\u3059\u3002<\/p>\n\n\n\n<pre><code>Account act = new Account(\"\u7530\u4e2d\", 50000);\nact = null;   \/\/ \u53c2\u7167\u3092\u5207\u308b \u2192 \u3053\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306f\u30ac\u30fc\u30d9\u30fc\u30b8\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306e\u5bfe\u8c61\u306b\u306a\u308b\n\nact = new Account(\"\u9234\u6728\", 30000);   \/\/ \u65b0\u3057\u3044\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306b\u53c2\u7167\u3092\u4ed8\u3051\u66ff\u3048<\/code><\/pre>\n\n\n\n<p>\u30ac\u30fc\u30d9\u30fc\u30b8\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306e\u30dd\u30a4\u30f3\u30c8\u306f<strong>\u300c\u5bfe\u8c61\u306b\u306a\u3063\u3066\u3082\u3001\u3059\u3050\u306b\u306f\u7834\u68c4\u3055\u308c\u306a\u3044\u300d<\/strong>\u3068\u3044\u3046\u70b9\u3067\u3059\u3002\u7834\u68c4\u3055\u308c\u308b\u30bf\u30a4\u30df\u30f3\u30b0\u306fJVM\u304c\u6c7a\u3081\u308b\u305f\u3081\u3001\u30d7\u30ed\u30b0\u30e9\u30e0\u304b\u3089\u5236\u5fa1\u3059\u308b\u3053\u3068\u306f\u3067\u304d\u307e\u305b\u3093\u3002\u300c<code>null<\/code> \u3092\u4ee3\u5165\u3057\u305f\u3089\u3059\u3050\u6d88\u3048\u308b\u300d\u3068\u601d\u3063\u3066\u3057\u307e\u3046\u521d\u5b66\u8005\u304c\u591a\u3044\u306e\u3067\u3001\u3053\u3053\u306f\u6ce8\u610f\u3057\u3066\u304a\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n<hr>\n\n\n<h2 class=\"wp-block-heading\" id=\"summary\">\u307e\u3068\u3081<\/h2>\n\n\n\n<p>\u4eca\u56de\u306fJava\u306e\u300c\u30af\u30e9\u30b9\u300d\u306b\u3064\u3044\u3066\u3001\u57fa\u790e\u306e\u57fa\u790e\u304b\u3089\u73fe\u5834\u3067\u4f7f\u3048\u308b\u77e5\u8b58\u307e\u3067\u89e3\u8aac\u3057\u307e\u3057\u305f\u3002\u6700\u5f8c\u306b\u30dd\u30a4\u30f3\u30c8\u3092\u6574\u7406\u3057\u3066\u304a\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\">\n<table>\n  <thead>\n    <tr>\n      <th>\u30c6\u30fc\u30de<\/th>\n      <th>\u30dd\u30a4\u30f3\u30c8<\/th>\n    <\/tr>\n  <\/thead>\n  <tbody>\n    <tr>\n      <td><strong>\u30af\u30e9\u30b9\u306e\u4fbf\u5229\u3055<\/strong><\/td>\n      <td>\u30c7\u30fc\u30bf\u3068\u30e1\u30bd\u30c3\u30c9\u3092\u3072\u3068\u307e\u3068\u3081\u306b\u3067\u304d\u308b\u3002\u73fe\u5b9f\u306e\u300c\u3082\u306e\u300d\u3092\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u8868\u73fe\u3067\u304d\u308b<\/td>\n    <\/tr>\n    <tr>\n      <td><strong>\u30af\u30e9\u30b9\u306e\u5b9a\u7fa9<\/strong><\/td>\n      <td><code>class \u30af\u30e9\u30b9\u540d { \u30d5\u30a3\u30fc\u30eb\u30c9 + \u30e1\u30bd\u30c3\u30c9 }<\/code>\u3002<code>this<\/code> \u306f\u81ea\u5206\u81ea\u8eab\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u6307\u3059<\/td>\n    <\/tr>\n    <tr>\n      <td><strong>\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5316<\/strong><\/td>\n      <td><code>new<\/code> \u6f14\u7b97\u5b50\u3067\u5b9f\u4f53\u3092\u751f\u6210\u3002<code>.<\/code>\uff08\u30c9\u30c3\u30c8\uff09\u3067\u30d5\u30a3\u30fc\u30eb\u30c9\u3084\u30e1\u30bd\u30c3\u30c9\u306b\u30a2\u30af\u30bb\u30b9<\/td>\n    <\/tr>\n    <tr>\n      <td><strong>\u30ab\u30d7\u30bb\u30eb\u5316<\/strong><\/td>\n      <td>\u30d5\u30a3\u30fc\u30eb\u30c9\u306f<code>private<\/code>\u3001\u30a2\u30af\u30bb\u30b9\u306f<code>public<\/code>\u306a\u30b2\u30c3\u30bf\u30fc\u30fb\u30bb\u30c3\u30bf\u30fc\u7d4c\u7531\u304c\u57fa\u672c<\/td>\n    <\/tr>\n    <tr>\n      <td><strong>\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf<\/strong><\/td>\n      <td><code>new<\/code> \u6642\u306b\u81ea\u52d5\u547c\u3073\u51fa\u3057\u3002\u30af\u30e9\u30b9\u540d\u3068\u540c\u540d\u30fb\u623b\u308a\u5024\u306a\u3057\u3002\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\u3082\u53ef\u80fd<\/td>\n    <\/tr>\n    <tr>\n      <td><strong>\u7528\u8a9e\u306e\u6574\u7406<\/strong><\/td>\n      <td>\u30af\u30e9\u30b9\uff08\u8a2d\u8a08\u56f3\uff09\u2192 new \u2192 \u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\uff08\u5b9f\u4f53\uff09\u3002\u30ac\u30fc\u30d9\u30fc\u30b8\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306fJVM\u304c\u81ea\u52d5\u7ba1\u7406<\/td>\n    <\/tr>\n  <\/tbody>\n<\/table>\n<\/figure>\n\n\n\n<p>\u30af\u30e9\u30b9\u306e\u6982\u5ff5\u306f\u3001\u6700\u521d\u306f\u5c11\u3057\u62bd\u8c61\u7684\u306b\u611f\u3058\u308b\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u3002\u3067\u3082<strong>\u300c\u9280\u884c\u53e3\u5ea7\u300d\u300c\u793e\u54e1\u300d\u300c\u5546\u54c1\u300d\u306a\u3069\u3001\u8eab\u8fd1\u306a&#8221;\u3082\u306e&#8221;\u3092\u30af\u30e9\u30b9\u3068\u3057\u3066\u66f8\u3044\u3066\u307f\u308b\u3053\u3068<\/strong>\u304c\u3001\u4e00\u756a\u306e\u8fd1\u9053\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u4eca\u65e5\u306e\u30b3\u30fc\u30c9\u4f8b\u3092\u81ea\u5206\u3067\u3082\u66f8\u3044\u3066\u52d5\u304b\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002\u624b\u3092\u52d5\u304b\u3059\u3053\u3068\u3067\u3001\u30af\u30e9\u30b9\u3068\u3044\u3046\u6982\u5ff5\u304c\u4f53\u306b\u67d3\u307f\u8fbc\u3093\u3067\u3044\u304d\u307e\u3059\u3002\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u6307\u5411\u306e\u6249\u306f\u3001\u3082\u3046\u3059\u3050\u305d\u3053\u3067\u3059\uff01<\/p>\n\n\n\n<p>\u6b21\u56de\u306f\u300c\u30af\u30e9\u30b9\u306e\u7d99\u627f\u3068\u30dd\u30ea\u30e2\u30fc\u30d5\u30a3\u30ba\u30e0\u300d\u306b\u3064\u3044\u3066\u89e3\u8aac\u4e88\u5b9a\u3067\u3059\u3002\u304a\u697d\u3057\u307f\u306b\uff01<\/p>\n\n","protected":false},"excerpt":{"rendered":"<p>\u300c\u30af\u30e9\u30b9\u3063\u3066\u5909\u6570\u3068\u30e1\u30bd\u30c3\u30c9\u3092\u307e\u3068\u3081\u305f\u3060\u3051\uff1f\u300d\u300c\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3068\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3063\u3066\u4f55\u304c\u9055\u3046\u306e\uff1f\u300d\u2014\u2014Java\u3092\u5b66\u3073\u59cb\u3081\u308b\u3068\u3001\u3053\u3046\u3044\u3063\u305f\u7591\u554f\u304c\u6b21\u3005\u3068\u6e67\u3044\u3066\u304d\u307e\u3059\u3088\u306d\u3002 \u5b9f\u306f\u3001\u30af\u30e9\u30b9\u3053\u305d\u304cJava\u306e\u6838\u5fc3\u3067\u3059\u3002\u30af\u30e9\u30b9\u3092\u7406\u89e3\u3067\u304d\u308b\u3068\u3001&hellip;<\/p>\n","protected":false},"author":1,"featured_media":424,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-418","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-7"],"_links":{"self":[{"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/418","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=418"}],"version-history":[{"count":1,"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/418\/revisions"}],"predecessor-version":[{"id":419,"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/418\/revisions\/419"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=\/wp\/v2\/media\/424"}],"wp:attachment":[{"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=418"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=418"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-third.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}