{"id":137389,"date":"2021-04-21T08:55:56","date_gmt":"2021-04-21T07:55:56","guid":{"rendered":"https:\/\/blog.jetbrains.com\/?post_type=kotlin&#038;p=137389"},"modified":"2021-04-21T09:02:50","modified_gmt":"2021-04-21T08:02:50","slug":"kotlin-1-4-30","status":"publish","type":"kotlin","link":"https:\/\/blog.jetbrains.com\/zh-hans\/kotlin\/2021\/04\/kotlin-1-4-30\/","title":{"rendered":"Kotlin 1.4.30 \u65b0\u7684\u8bed\u8a00\u529f\u80fd\u9884\u89c8"},"content":{"rendered":"<p>\u6211\u4eec\u8ba1\u5212\u5728 Kotlin 1.5 \u4e2d\u6dfb\u52a0\u4e00\u4e9b\u65b0\u7684\u8bed\u8a00\u529f\u80fd\uff0c\u4f46\u60a8\u73b0\u5728\u5c31\u53ef\u4ee5\u5728 Kotlin 1.4.30 \u4e2d\u8bd5\u7528\u8fd9\u4e9b\u529f\u80fd\uff1a<\/p>\n<ul>\n<li><a href=\"https:\/\/blog.jetbrains.com\/zh-hans\/kotlin\/2021\/04\/kotlin-1-4-30\/#inline-value-classes-stabilization\">\u5185\u8054 value \u7c7b\u7684\u7a33\u5b9a\u5316<\/a><\/li>\n<li><a href=\"https:\/\/blog.jetbrains.com\/zh-hans\/kotlin\/2021\/04\/kotlin-1-4-30\/#jvm-records\">\u5bf9 JVM \u8bb0\u5f55\u7684\u5b9e\u9a8c\u6027\u652f\u6301<\/a><\/li>\n<li><a href=\"https:\/\/blog.jetbrains.com\/zh-hans\/kotlin\/2021\/04\/kotlin-1-4-30\/#sealed-interfaces\">\u5bf9\u5bc6\u5c01\u63a5\u53e3\u7684\u5b9e\u9a8c\u6027\u652f\u6301\u548c\u5bf9\u5bc6\u5c01\u7c7b\u7684\u5176\u4ed6\u6539\u8fdb<\/a><\/li>\n<\/ul>\n<p>\u8981\u8bd5\u7528\u8fd9\u4e9b\u65b0\u529f\u80fd\uff0c\u60a8\u9700\u8981 <a href=\"https:\/\/blog.jetbrains.com\/zh-hans\/kotlin\/2021\/04\/kotlin-1-4-30\/#how-to-try\">\u6307\u5b9a 1.5 \u8bed\u8a00\u7248\u672c<\/a>\u3002<\/p>\n<p>\u65b0\u7684<a href=\"https:\/\/blog.jetbrains.com\/kotlin\/2020\/10\/new-release-cadence-for-kotlin-and-the-intellij-kotlin-plugin\/\">\u53d1\u5e03\u8282\u594f<\/a>\u610f\u5473\u7740 Kotlin 1.5 \u5c06\u5728\u51e0\u4e2a\u6708\u540e\u63a8\u51fa\uff0c\u4f46\u65b0\u529f\u80fd\u5df2\u7ecf\u53ef\u4ee5\u5728 1.4.30 \u4e2d\u9884\u89c8\u3002 \u60a8\u7684\u65e9\u671f\u53cd\u9988\u5bf9\u6211\u4eec\u81f3\u5173\u91cd\u8981\uff0c\u56e0\u6b64\u8bf7\u7acb\u5373\u5c1d\u8bd5\u8fd9\u4e9b\u65b0\u529f\u80fd\uff01<\/p>\n<p><a href=\"https:\/\/youtrack.jetbrains.com\/issues?q=tag:%20Language\" target=\"_blank\" rel=\"noopener\"><img decoding=\"async\" src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2021\/02\/Kotlin-1.4.30-new-lang-features-banner_2-02.png\" alt=\"\" \/><\/a><\/p>\n<h2>\u5185\u8054 value \u7c7b\u7684\u7a33\u5b9a\u5316<\/h2>\n<p><a name = \"inline-value-classes-stabilization\"><\/a><\/p>\n<p>\u81ea Kotlin 1.3 \u5f00\u59cb\uff0c<a href=\"https:\/\/kotlinlang.org\/docs\/reference\/inline-classes.html\" target=\"_blank\" rel=\"noopener\">\u5185\u8054\u7c7b<\/a>\u5373\u5904\u4e8e <a href=\"https:\/\/kotlinlang.org\/docs\/reference\/evolution\/components-stability.html#stability-levels-explained\" target=\"_blank\" rel=\"noopener\">Alpha<\/a> \u9636\u6bb5\uff0c\u76f4\u5230\u5728 1.4.30 \u4e2d\u88ab\u63d0\u5347\u5230 <a href=\"https:\/\/kotlinlang.org\/docs\/reference\/evolution\/components-stability.html#stability-levels-explained\" target=\"_blank\" rel=\"noopener\">Beta<\/a> \u9636\u6bb5\u3002<\/p>\n<p>Kotlin 1.5 \u7a33\u5b9a\u4e86\u5185\u8054\u7c7b\u7684\u6982\u5ff5\uff0c\u4f46\u4f7f\u5176\u6210\u4e3a\u66f4\u901a\u7528\u7684\u7279\u6027 &#8211;value \u7c7b\u7684\u4e00\u90e8\u5206\uff0c\u6211\u4eec\u5c06\u5728\u540e\u6587\u4ecb\u7ecd\u3002<\/p>\n<p>\u6211\u4eec\u5148\u6765\u8c08\u4e00\u8c08\u5185\u8054\u7c7b\u7684\u5de5\u4f5c\u539f\u7406\u3002 \u5982\u679c\u60a8\u5df2\u7ecf\u719f\u6089\u5185\u8054\u7c7b\uff0c\u90a3\u4e48\u53ef\u4ee5\u8df3\u8fc7\u672c\u90e8\u5206\uff0c\u76f4\u63a5\u8fdb\u5165<a href=\"#jvm-name-support\">\u65b0\u53d8\u5316<\/a>\u3002<\/p>\n<p>\u9996\u5148\uff0c\u5185\u8054\u7c7b\u6d88\u9664\u4e86\u503c\u5468\u56f4\u7684\u5305\u88c5\u5668\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\ninline class Color(val rgb: Int)\r\n<\/pre>\n<p>\u5185\u8054\u7c7b\u65e2\u53ef\u4ee5\u662f\u57fa\u5143\u7c7b\u578b\u7684\u5305\u88c5\u5668\uff0c\u4e5f\u53ef\u4ee5\u662f\u4efb\u4f55\u5f15\u7528\u7c7b\u578b\u7684\u5305\u88c5\u5668\uff0c\u5982 <code>String<\/code>\u3002<\/p>\n<p>\u7f16\u8bd1\u5668\u5728\u53ef\u80fd\u7684\u60c5\u51b5\u4e0b\uff0c\u4f1a\u5728\u5b57\u8282\u7801\u4e2d\u7528\u5e95\u5c42\u7c7b\u578b (<code>Int<\/code>) \u66ff\u6362\u5185\u8054\u7c7b\u5b9e\u4f8b\uff08\u5728\u6211\u4eec\u7684\u793a\u4f8b\u4e2d\u4e3a <code>Color<\/code> \u5b9e\u4f8b\uff09:<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\nfun changeBackground(color: Color) \r\nval blue = Color(255)\r\nchangeBackground(blue)\r\n<\/pre>\n<p>\u5728\u540e\u53f0\uff0c\u7f16\u8bd1\u5668\u751f\u6210\u540d\u79f0\u7ecf\u8fc7\u4fee\u9970\u7684 <code>changeBackground<\/code> \u51fd\u6570\uff0c\u5b83\u4ee5 <code>Int<\/code> \u4e3a\u53c2\u6570\uff0c\u76f4\u63a5\u4f20\u9012 <code>255<\/code> \u5e38\u91cf\uff0c\u800c\u4e0d\u5728\u8c03\u7528\u70b9\u521b\u5efa\u5305\u88c5\u5668\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\nfun changeBackground-euwHqFQ(color: Int) \r\nchangeBackground-euwHqFQ(255) \/\/ no extra object is allocated! \r\n<\/pre>\n<p>\u540d\u79f0\u7ecf\u8fc7\u4fee\u9970\uff0c\u4ee5\u5141\u8bb8\u91c7\u7528\u4e0d\u540c\u5185\u8054\u7c7b\u7684\u5b9e\u4f8b\u7684\u51fd\u6570\u65e0\u7f1d\u91cd\u8f7d\uff0c\u9632\u6b62\u53ef\u80fd\u4f1a\u8fdd\u53cd\u5185\u8054\u7c7b\u5185\u90e8\u7ea6\u675f\u7684 Java \u4ee3\u7801\u7684\u610f\u5916\u8c03\u7528\u3002 \u9605\u8bfb<a href=\"#jvm-name-support\">\u4e0b\u6587<\/a>\uff0c\u4e86\u89e3\u5982\u4f55\u4ece Java \u4e2d\u4f7f\u5176\u53ef\u7528\u3002<br \/>\n\u5305\u88c5\u5668\u5e76\u4e0d\u603b\u662f\u5728\u5b57\u8282\u7801\u4e2d\u6d88\u9664\u3002 \u8fd9\u4ec5\u5728\u53ef\u80fd\u7684\u60c5\u51b5\u4e0b\u53d1\u751f\uff0c\u5e76\u4e14\u4e0e\u5185\u7f6e\u57fa\u5143\u7c7b\u578b\u975e\u5e38\u76f8\u4f3c\u3002 \u5b9a\u4e49 <code>Color<\/code> \u7c7b\u578b\u7684\u53d8\u91cf\u6216\u5c06\u5176\u76f4\u63a5\u4f20\u9012\u5230\u51fd\u6570\u65f6\uff0c\u5b83\u5c06\u88ab\u5e95\u5c42\u503c\u66ff\u6362\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\nval color = Color(0)        \/\/ primitive\r\nchangeBackground(color)     \/\/ primitive\r\n<\/pre>\n<p>\u5728\u6b64\u793a\u4f8b\u4e2d\uff0c<code>color<\/code> \u53d8\u91cf\u5728\u7f16\u8bd1\u671f\u95f4\u7684\u7c7b\u578b\u4e3a <code>Color<\/code>\uff0c\u4f46\u5728\u5b57\u8282\u7801\u4e2d\u88ab\u66ff\u6362\u4e3a <code>Int<\/code>\u3002<\/p>\n<p>\u4f46\u662f\uff0c\u5982\u679c\u60a8\u5c06\u5176\u5b58\u50a8\u5728\u96c6\u5408\u4e2d\u6216\u4f20\u9012\u5230\u6cdb\u578b\u51fd\u6570\uff0c\u5b83\u5c06\u88c5\u7bb1\u5230 <code>Color<\/code> \u7c7b\u578b\u7684\u5e38\u89c4\u5bf9\u8c61\u4e2d\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\ngenericFunc(color)         \/\/ boxed\r\nval list = listOf(color)   \/\/ boxed\r\nval first = list.first()   \/\/ unboxed back to primitive\r\n<\/pre>\n<p>\u88c5\u7bb1\u548c\u62c6\u7bb1\u7531\u7f16\u8bd1\u5668\u81ea\u52a8\u5b8c\u6210\u3002 \u867d\u7136\u60a8\u4e0d\u5fc5\u4e0a\u624b\uff0c\u4f46\u4e86\u89e3\u4e00\u4e0b\u5185\u90e8\u60c5\u51b5\u4e5f\u662f\u6709\u6240\u88e8\u76ca\u7684\u3002<\/p>\n<h3>\u66f4\u6539 Java \u8c03\u7528\u7684 JVM \u540d\u79f0<\/h3>\n<p><a name = \"jvm-name-support\"><\/a><\/p>\n<p>\u4ece 1.4.30 \u5f00\u59cb\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u5185\u8054\u7c7b\u4f5c\u4e3a\u53c2\u6570\u66f4\u6539\u51fd\u6570\u7684 JVM \u540d\u79f0\uff0c\u4f7f\u5176\u53ef\u4ece Java \u4f7f\u7528\u3002 \u6b64\u7c7b\u540d\u79f0\u9ed8\u8ba4\u7ecf\u8fc7\u4fee\u9970\uff0c\u4ee5\u9632\u6b62 Java \u610f\u5916\u4f7f\u7528\u6216\u51b2\u7a81\u7684\u91cd\u8f7d\uff08\u4f8b\u5982\u4e0a\u4f8b\u4e2d\u7684 <code>changeBackground-euwHqFQ<\/code>\uff09\u3002<\/p>\n<p>\u5982\u679c\u4f7f\u7528 <code>@JvmName<\/code> \u6ce8\u89e3\u51fd\u6570\uff0c\u5b83\u5c06\u5728\u5b57\u8282\u7801\u4e2d\u66f4\u6539\u6b64\u51fd\u6570\u7684\u540d\u79f0\uff0c\u4f7f\u5176\u53ef\u4ece Java \u8c03\u7528\u5e76\u76f4\u63a5\u4f20\u9012\u503c\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\n\/\/ Kotlin declarations\r\ninline class Timeout(val millis: Long)\r\n\r\nval Int.millis get() = Timeout(this.toLong())\r\nval Int.seconds get() = Timeout(this * 1000L)\r\n\r\n@JvmName(&quot;greetAfterTimeoutMillis&quot;)\r\nfun greetAfterTimeout(timeout: Timeout)\r\n\r\n\/\/ Kotlin usage\r\ngreetAfterTimeout(2.seconds)\r\n\r\n\/\/ Java usage\r\ngreetAfterTimeoutMillis(2000);\r\n<\/pre>\n<p>\u4e0e\u901a\u5e38\u4ee5 <code>@JvmName<\/code> \u6ce8\u89e3\u7684\u51fd\u6570\u4e00\u6837\uff0c\u5728 Kotlin \u4e2d\uff0c\u60a8\u53ef\u4ee5\u901a\u8fc7\u5176 Kotlin \u540d\u79f0\u8fdb\u884c\u8c03\u7528\u3002 Kotlin \u7528\u6cd5\u662f\u7c7b\u578b\u5b89\u5168\u7684\uff0c\u56e0\u4e3a\u60a8\u53ea\u80fd\u5c06 <code>Timeout<\/code> \u7c7b\u578b\u7684\u503c\u4f5c\u4e3a\u53c2\u6570\u4f20\u9012\uff0c\u5e76\u4e14\u5355\u4f4d\u5728\u7528\u6cd5\u4e2d\u53ef\u89c1\u3002<\/p>\n<p>\u60a8\u53ef\u4ee5\u4ece Java \u76f4\u63a5\u4f20\u9012 <code>long<\/code> \u503c\u3002 \u5b83\u4e0d\u518d\u662f\u7c7b\u578b\u5b89\u5168\u7684\uff0c\u4e5f\u56e0\u6b64\u9ed8\u8ba4\u4e0d\u5de5\u4f5c\u3002 \u5bf9\u4e8e\u4ee3\u7801\u4e2d\u7684 <code>greetAfterTimeout(2)<\/code>\uff0c\u60a8\u5f88\u96be\u7acb\u5373\u770b\u51fa\u662f 2 \u79d2\u30012 \u6beb\u79d2\u8fd8\u662f 2 \u5e74\u3002<\/p>\n<p>\u901a\u8fc7\u63d0\u4f9b\u6ce8\u89e3\uff0c\u60a8\u660e\u786e\u5f3a\u8c03\u8981\u4ece Java \u8c03\u7528\u6b64\u51fd\u6570\u3002 \u63cf\u8ff0\u6027\u540d\u79f0\u6709\u52a9\u4e8e\u907f\u514d\u6df7\u6dc6\uff1a\u5728 JVM \u540d\u79f0\u4e2d\u6dfb\u52a0\u201cMillis\u201d\u540e\u7f00\uff0c\u8ba9 Java \u7528\u6237\u6e05\u695a\u4e86\u89e3\u8fd9\u4e9b\u5355\u4f4d\u3002<\/p>\n<h3>Init blocks<\/h3>\n<p><a name = \"init-blocks\"><\/a><\/p>\n<p>1.4.30 \u4e2d\u5185\u8054\u7c7b\u7684\u53e6\u4e00\u4e2a\u6539\u8fdb\u662f\uff0c\u60a8\u73b0\u5728\u53ef\u4ee5\u5728 <code>init<\/code> \u5757\u4e2d\u5b9a\u4e49\u521d\u59cb\u5316\u903b\u8f91\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\ninline class Name(val s: String) {\r\n   init {\r\n       require(s.isNotEmpty())\r\n   }\r\n}\r\n<\/pre>\n<p>\u8fd9\u5728\u8fc7\u53bb\u662f\u4e0d\u88ab\u5141\u8bb8\u7684\u3002<br \/>\n\u60a8\u53ef\u4ee5\u5728\u76f8\u5e94\u7684 <a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/proposals\/inline-classes.md\" target=\"_blank\" rel=\"noopener\">KEEP<\/a>\u3001<a href=\"https:\/\/kotlinlang.org\/docs\/reference\/whatsnew1430.html#improved-inline-classes\" target=\"_blank\" rel=\"noopener\">\u6587\u6863<\/a>\u548c\u6b64<a href=\"https:\/\/kotlinlang.org\/docs\/reference\/whatsnew1430.html#improved-inline-classes\" target=\"_blank\" rel=\"noopener\">\u95ee\u9898<\/a>\u4e0b\u7684\u8ba8\u8bba\u4e2d\u9605\u8bfb\u6709\u5173\u5185\u8054\u7c7b\u7684\u66f4\u591a\u8be6\u7ec6\u4fe1\u606f\u3002<\/p>\n<h3>\u5185\u8054 value \u7c7b<\/h3>\n<p><a name = \"inline-value-classes\"><\/a><\/p>\n<p>Kotlin 1.5 \u7a33\u5b9a\u4e86\u5185\u8054\u7c7b\u7684\u6982\u5ff5\uff0c\u5e76\u4f7f\u5176\u6210\u4e3a\u66f4\u901a\u7528\u7684\u7279\u6027 value \u7c7b\u7684\u4e00\u90e8\u5206\u3002<\/p>\n<p>\u201c\u5185\u8054\u7c7b\u201d\u6b64\u524d\u4e00\u76f4\u662f\u4e00\u9879\u5355\u72ec\u7684\u8bed\u8a00\u529f\u80fd\uff0c\u4f46\u73b0\u5728\u6b63\u6210\u4e3a\u9488\u5bf9\u542b\u4e00\u4e2a\u53c2\u6570\u7684 value \u7c7b\u7684\u7279\u5b9a JVM \u4f18\u5316\u3002 value \u7c7b\u4ee3\u8868\u4e86\u4e00\u4e2a\u66f4\u901a\u7528\u7684\u6982\u5ff5\uff0c\u5e76\u4e14\u5c06\u652f\u6301\u4e0d\u540c\u7684\u4f18\u5316\uff1a\u73b0\u5728\u662f\u5185\u8054\u7c7b\uff0c\u672a\u6765\u5f53 Valhalla \u9879\u76ee\u53ef\u7528\u65f6\u5c06\u652f\u6301 Valhalla \u57fa\u5143\u7c7b\uff08<a href=\"https:\/\/blog.jetbrains.com\/zh-hans\/kotlin\/2021\/04\/kotlin-1-4-30\/#valhalla\">\u4e0b\u6587<\/a>\u5c06\u8be6\u7ec6\u4ecb\u7ecd\uff09\u3002<\/p>\n<p>\u76ee\u524d\u5bf9\u60a8\u6765\u8bf4\uff0c\u552f\u4e00\u6539\u53d8\u7684\u662f\u8bed\u6cd5\u3002 \u7531\u4e8e\u5185\u8054\u7c7b\u662f\u4f18\u5316\u7684 value \u7c7b\uff0c\u60a8\u5fc5\u987b\u4f7f\u7528\u4e0e\u4ee5\u5f80\u4e0d\u540c\u7684\u65b9\u5f0f\u58f0\u660e\u5b83\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\n@JvmInline\r\nvalue class Color(val rgb: Int)\r\n<\/pre>\n<p>\u53ef\u4ee5\u4f7f\u7528\u4e00\u4e2a\u6784\u9020\u51fd\u6570\u53c2\u6570\u5b9a\u4e49\u4e00\u4e2a value \u7c7b\uff0c\u5e76\u4ee5 <code>@JvmInline<\/code> \u6ce8\u89e3\u3002 \u6211\u4eec\u5e0c\u671b\u6240\u6709\u4eba\u90fd\u53ef\u4ee5\u4ece Kotlin 1.5 \u5f00\u59cb\u4f7f\u7528\u8fd9\u79cd\u65b0\u8bed\u6cd5\u3002 \u65e7\u8bed\u6cd5 <code>inline class<\/code> \u5c06\u7ee7\u7eed\u5de5\u4f5c\u4e00\u6bb5\u65f6\u95f4\u3002 \u5b83\u5c06\u5728 1.5 \u4e2d\u88ab\u5f03\u7528\uff0c\u5e76\u663e\u793a\u8b66\u544a\uff0c1.5 \u7248\u672c\u4e2d\u5c06\u5305\u542b\u4e00\u4e2a\u81ea\u52a8\u8fc1\u79fb\u6240\u6709\u58f0\u660e\u7684\u9009\u9879\u3002 \u540e\u7eed\u5c06\u53d8\u4e3a\u5e26\u6709\u9519\u8bef\u7684\u5f03\u7528\u3002<\/p>\n<h2>Value \u7c7b<\/h2>\n<p><a name = \"value-classes\"><\/a><\/p>\n<p><code>value<\/code> \u7c7b\u8868\u793a\u5177\u6709\u6570\u636e\u7684\u4e0d\u53ef\u53d8\u5b9e\u4f53\u3002 \u76ee\u524d\uff0c\u4e00\u4e2a <code>value<\/code> \u7c7b\u53ea\u80fd\u5305\u542b\u4e00\u4e2a\u5c5e\u6027\u6765\u652f\u6301\u201c\u65e7\u201d\u5185\u8054\u7c7b\u7684\u7528\u4f8b\u3002<\/p>\n<p>\u5728\u672a\u6765\u5b8c\u5168\u652f\u6301\u6b64\u529f\u80fd\u7684 Kotlin \u7248\u672c\u4e2d\uff0c\u5c06\u53ef\u4ee5\u5b9a\u4e49\u5177\u6709\u8bb8\u591a\u5c5e\u6027\u7684 value \u7c7b\u3002 \u6240\u6709\u503c\u5747\u5e94\u4e3a\u53ea\u8bfb <code>val<\/code>\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\nvalue class Point(val x: Int, val y: Int)\r\n<\/pre>\n<p>value \u7c7b\u6ca1\u6709\u8eab\u4efd\uff1a\u5b83\u4eec\u5b8c\u5168\u7531\u5b58\u50a8\u7684\u6570\u636e\u5b9a\u4e49\uff0c\u5e76\u4e14\u4e0d\u53ef\u63a5\u53d7 === \u8eab\u4efd\u68c0\u67e5\u3002 == \u76f8\u7b49\u6027\u68c0\u67e5\u4f1a\u81ea\u52a8\u6bd4\u8f83\u5e95\u5c42\u6570\u636e\u3002<\/p>\n<p>value \u7c7b\u7684\u8fd9\u79cd\u201c\u65e0\u8eab\u4efd\u201d\u7279\u8d28\u4e3a\u672a\u6765\u7684\u91cd\u5927\u4f18\u5316\u5960\u5b9a\u4e86\u57fa\u7840\uff1a\u5728 Valhalla \u9879\u76ee\u8fdb\u5165 JVM \u540e\uff0c\u5c06\u5141\u8bb8 value \u7c7b\u5728\u540e\u53f0\u4f5c\u4e3a JVM \u57fa\u5143\u7c7b\u5b9e\u73b0\u3002<\/p>\n<p>\u4e0d\u53d8\u6027\u7ea6\u675f\u4ee5\u53ca Valhalla \u4f18\u5316\u7684\u53ef\u80fd\u6027\u4f7f <code>value<\/code> \u7c7b\u4e0d\u540c\u4e8e <code>data<\/code> \u7c7b\u3002<\/p>\n<h3>\u672a\u6765 Valhalla \u4f18\u5316<\/h3>\n<p><a name = \"valhalla\"><\/a><\/p>\n<p><a href=\"https:\/\/openjdk.java.net\/jeps\/8251554\" target=\"_blank\" rel=\"noopener\">Valhalla \u9879\u76ee<\/a> \u4e3a Java \u548c JVM \u5f15\u5165\u4e86\u4e00\u4e2a\u65b0\u6982\u5ff5\uff1a\u57fa\u5143\u7c7b\u3002<\/p>\n<p>\u57fa\u5143\u7c7b\u7684\u4e3b\u8981\u76ee\u6807\u662f\u5c06\u57fa\u5143\u7684\u9ad8\u6027\u80fd\u4e0e\u5e38\u89c4 JVM \u7c7b\u7684\u5bf9\u8c61\u5bfc\u5411\u4f18\u52bf\u76f8\u7ed3\u5408\u3002 \u57fa\u5143\u7c7b\u662f\u6570\u636e\u6301\u6709\u8005\uff0c\u5176\u5b9e\u4f8b\u53ef\u4ee5\u5b58\u50a8\u5728\u8ba1\u7b97\u5806\u6808\u4e0a\u7684\u53d8\u91cf\u4e2d\uff0c\u5e76\u4e14\u53ef\u4ee5\u76f4\u63a5\u64cd\u4f5c\uff0c\u6ca1\u6709\u5934\u548c\u6307\u9488\u3002 \u5728\u8fd9\u65b9\u9762\uff0c\u5b83\u4eec\u7c7b\u4f3c\u4e8e <code>int<\/code>\u3001<code>long<\/code> \u7b49\u57fa\u5143\u503c\uff08\u5728 Kotlin \u4e2d\uff0c\u60a8\u4e0d\u76f4\u63a5\u4f7f\u7528\u57fa\u5143\u7c7b\u578b\uff0c\u800c\u662f\u7531\u7f16\u8bd1\u5668\u5728\u540e\u53f0\u751f\u6210\uff09\u3002<\/p>\n<p>\u57fa\u5143\u7c7b\u7684\u4e00\u4e2a\u91cd\u8981\u4f18\u70b9\u662f\uff0c\u5b83\u4eec\u5141\u8bb8\u5185\u5b58\u4e2d\u5bf9\u8c61\u7684\u6241\u5e73\u548c\u5bc6\u96c6\u5e03\u5c40\u3002 \u76ee\u524d\uff0c<code>Array&lt;Point&gt;<\/code> \u662f\u5f15\u7528\u7684\u6570\u7ec4\u3002 \u501f\u52a9 Valhalla \u652f\u6301\uff0c\u5728\u5c06 <code>Point<\/code> \u5b9a\u4e49\u4e3a\u57fa\u5143\u7c7b\uff08Java \u672f\u8bed\uff09\u6216\u5b9a\u4e49\u4e3a\u5177\u6709\u5e95\u5c42\u4f18\u5316\u7684 value \u7c7b\uff08Kotlin \u672f\u8bed\uff09\u65f6\uff0cJVM \u53ef\u4ee5\u5bf9\u5176\u8fdb\u884c\u4f18\u5316\uff0c\u5e76\u5c06 <code>Point<\/code> \u7684\u6570\u7ec4\u4ee5\u201c\u6241\u5e73\u201d\u5e03\u5c40\u5b58\u50a8\uff0c\u76f4\u63a5\u4f5c\u4e3a\u7531\u8bb8\u591a <code>x<\/code> \u548c <code>y<\/code> \u7ec4\u6210\u7684\u6570\u7ec4\uff0c\u800c\u4e0d\u662f\u4f5c\u4e3a\u5f15\u7528\u6570\u7ec4\u3002<\/p>\n<p>\u6211\u4eec\u975e\u5e38\u671f\u5f85\u5373\u5c06\u5230\u6765\u7684 JVM \u53d8\u5316\uff0c\u6211\u4eec\u5e0c\u671b Kotlin \u80fd\u4ece\u4e2d\u53d7\u76ca\u3002 \u540c\u65f6\uff0c\u6211\u4eec\u4e0d\u60f3\u5f3a\u8feb\u793e\u533a\u4f9d\u8d56\u65b0\u7684 JVM \u7248\u672c\u624d\u80fd\u4f7f\u7528 value \u7c7b\uff0c\u6240\u4ee5\u6211\u4eec\u4e5f\u5c06\u4e3a\u8f83\u65e9\u7684 JVM \u7248\u672c\u63d0\u4f9b\u652f\u6301\u3002 \u5728\u5c06\u4ee3\u7801\u7f16\u8bd1\u5230\u652f\u6301 Valhalla \u7684 JVM \u65f6\uff0c\u6700\u65b0\u7684 JVM \u4f18\u5316\u5c06\u9002\u7528\u4e8e <code>value<\/code> \u7c7b\u3002<\/p>\n<h3>\u7a81\u53d8\u65b9\u6cd5<\/h3>\n<p><a name = \"mutating-methods\"><\/a><\/p>\n<p>\u5173\u4e8e value \u7c7b\u7684\u529f\u80fd\uff0c\u8fd8\u6709\u8bb8\u591a\u503c\u5f97\u4ecb\u7ecd\u3002 \u7531\u4e8e value \u7c7b\u8868\u793a\u201c\u4e0d\u53ef\u53d8\u201d\u6570\u636e\uff0c\u56e0\u6b64\u53ef\u4ee5\u4f7f\u7528\u7a81\u53d8\u65b9\u6cd5\uff08\u4f8b\u5982 <a href=\"https:\/\/docs.swift.org\/swift-book\/LanguageGuide\/Methods.html\" target=\"_blank\" rel=\"noopener\">Swift<\/a> \u4e2d\u7684\u7a81\u53d8\u65b9\u6cd5\uff09\u3002 \u7a81\u53d8\u65b9\u6cd5\u662f\u6307\u6210\u5458\u51fd\u6570\u6216\u5c5e\u6027 setter \u8fd4\u56de\u65b0\u5b9e\u4f8b\u800c\u4e0d\u662f\u66f4\u65b0\u73b0\u6709\u5b9e\u4f8b\uff0c\u4e3b\u8981\u597d\u5904\u662f\u60a8\u53ef\u4ee5\u91c7\u7528\u719f\u6089\u7684\u8bed\u6cd5\u3002 \u8fd9\u4ecd\u7136\u9700\u8981\u5728\u8bed\u8a00\u4e2d\u8fdb\u884c\u539f\u578b\u8bbe\u8ba1\u3002<\/p>\n<h3>\u66f4\u591a\u8be6\u7ec6\u4fe1\u606f<\/h3>\n<p><a name = \"read-more-value-classes\"><\/a><\/p>\n<p><code>@JvmInline<\/code> \u6ce8\u89e3\u662f\u7279\u5b9a\u4e8e JVM \u7684\u3002 \u5728\u5176\u4ed6\u540e\u7aef\uff0cvalue \u7c7b\u53ef\u4ee5\u7531\u4e0d\u540c\u7684\u65b9\u5f0f\u5b9e\u73b0\u3002 \u4f8b\u5982 Kotlin\/Native \u4e2d\u7684 Swift \u7ed3\u6784\u3002<\/p>\n<p>\u60a8\u53ef\u4ee5\u5728 Kotlin value \u7c7b\u7684<a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/notes\/value-classes.md\" target=\"_blank\" rel=\"noopener\">\u8bbe\u8ba1\u8bf4\u660e<\/a>\u4e2d\u9605\u8bfb\u6709\u5173 value \u7c7b\u7684\u8be6\u7ec6\u4fe1\u606f\uff0c\u6216\u89c2\u770b Roman Elizarov \u7684<a href=\"https:\/\/www.youtube.com\/watch?v=0FF19HJDqMo&amp;t=26m32s\" target=\"_blank\" rel=\"noopener\">\u201c\u5c55\u671b\u672a\u6765\u201d<\/a>\u6f14\u8bb2\u8282\u9009\u3002<\/p>\n<h2>\u652f\u6301 JVM \u8bb0\u5f55<\/h2>\n<p><a name = \"jvm-records\"><\/a><\/p>\n<p>JVM \u751f\u6001\u7cfb\u7edf\u4e2d\u5c06\u8fce\u6765\u7684\u53e6\u4e00\u9879\u6539\u8fdb\u662f <a href=\"https:\/\/openjdk.java.net\/jeps\/395\" target=\"_blank\" rel=\"noopener\">Java \u8bb0\u5f55<\/a>\u3002 \u5b83\u4eec\u7c7b\u4f3c\u4e8e Kotlin data \u7c7b\uff0c\u4e3b\u8981\u7528\u4f5c\u7b80\u5355\u7684\u6570\u636e\u6301\u6709\u8005\u3002<\/p>\n<p>Java records don\u2019t follow the JavaBeans convention, and they have <code>x()<\/code> and <code>y()<\/code> methods instead of the familiar <code>getX()<\/code> and <code>getY()<\/code>.<\/p>\n<p>\u4e0e Java \u7684\u4e92\u64cd\u4f5c\u6027\u4e00\u76f4\u4ee5\u6765\u90fd\u662f\u5e76\u4e14\u5c06\u6c38\u8fdc\u4f5c\u4e3a Kotlin \u7684\u4f18\u5148\u8003\u8651\u4e8b\u9879\u3002 \u56e0\u6b64\uff0cKotlin \u4ee3\u7801\u53ef\u4ee5\u201c\u7406\u89e3\u201d\u65b0\u7684 Java \u8bb0\u5f55\uff0c\u5e76\u5c06\u5176\u89c6\u4e3a\u5177\u6709 Kotlin \u5c5e\u6027\u7684\u7c7b\u3002 \u8fd9\u7c7b\u4f3c\u4e8e\u9075\u5faa JavaBeans \u60ef\u4f8b\u7684\u5e38\u89c4 Java \u7c7b\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\n\/\/ Java\r\nrecord Point(int x, int y) { }\r\n\/\/ Kotlin\r\nfun foo(point: Point) {\r\n    point.x \/\/ seen as property\r\n    point.x() \/\/ also works\r\n}\r\n<\/pre>\n<p>\u4e3b\u8981\u51fa\u4e8e\u4e92\u64cd\u4f5c\u6027\uff0c\u60a8\u53ef\u4ee5\u7528 <code>@JvmRecord<\/code> \u6ce8\u89e3 <code>data<\/code> \u7c7b\uff0c\u751f\u6210\u65b0\u7684 JVM \u8bb0\u5f55\u65b9\u6cd5\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\n@JvmRecord\r\ndata class Point(val x: Int, val y: Int)\r\n<\/pre>\n<p><code>@JvmRecord<\/code> \u6ce8\u89e3\u4f7f\u7f16\u8bd1\u5668\u751f\u6210 <code>x()<\/code> \u548c <code>y()<\/code> \u65b9\u6cd5\uff0c\u800c\u4e0d\u662f\u6807\u51c6\u7684 <code>getX()<\/code> \u548c <code>getY()<\/code> \u65b9\u6cd5\u3002 \u6211\u4eec\u5047\u8bbe\u60a8\u53ea\u9700\u8981\u5728\u5c06\u7c7b\u4ece Java \u8f6c\u6362\u5230 Kotlin \u65f6\u4f7f\u7528\u6b64\u6ce8\u89e3\u4fdd\u5b58\u7c7b\u7684 API\u3002 \u5728\u6240\u6709\u5176\u4ed6\u7528\u4f8b\u4e2d\uff0c\u90fd\u53ef\u4ee5\u4f7f\u7528 Kotlin \u5e38\u89c1\u7684 data \u7c7b\uff0c\u800c\u4e0d\u4f1a\u51fa\u73b0\u95ee\u9898\u3002<\/p>\n<p>\u53ea\u6709\u5c06 Kotlin \u4ee3\u7801\u7f16\u8bd1\u5230 JVM 15 \u4ee5\u4e0a\u7248\u672c\u65f6\uff0c\u6b64\u6ce8\u89e3\u624d\u53ef\u7528\u3002 \u60a8\u53ef\u4ee5\u5728\u76f8\u5e94\u7684 <a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/proposals\/jvm-records.md\" target=\"_blank\" rel=\"noopener\">KEEP<\/a>\u3001<a href=\"https:\/\/kotlinlang.org\/docs\/reference\/whatsnew1430.html#jvm-records-support\" target=\"_blank\" rel=\"noopener\">\u6587\u6863<\/a>\u548c\u6b64<a href=\"https:\/\/youtrack.jetbrains.com\/issue\/KT-42430\" target=\"_blank\" rel=\"noopener\">\u95ee\u9898<\/a>\u4e0b\u7684\u8ba8\u8bba\u4e2d\u9605\u8bfb\u6709\u5173\u6b64\u529f\u80fd\u7684\u66f4\u591a\u8be6\u7ec6\u4fe1\u606f\u3002<\/p>\n<h2>\u5bc6\u5c01\u63a5\u53e3\u548c\u5bc6\u5c01\u7c7b\u7684\u6539\u8fdb<\/h2>\n<p><a name = \"sealed-interfaces\"><\/a><\/p>\n<p>\u4f7f\u7c7b\u5bc6\u5c01\u65f6\uff0c\u5b83\u4f1a\u5c06\u5c42\u6b21\u7ed3\u6784\u9650\u5236\u4e3a\u5df2\u5b9a\u4e49\u7684\u5b50\u7c7b\uff0c\u4ece\u800c\u5141\u8bb8\u5728 <code>when<\/code> \u5206\u652f\u4e2d\u8fdb\u884c\u8be6\u5c3d\u7684\u68c0\u67e5\u3002 \u5728 Kotlin 1.4 \u4e2d\uff0c\u5bc6\u5c01\u7c7b\u5c42\u6b21\u7ed3\u6784\u5177\u6709\u4e24\u4e2a\u7ea6\u675f\u3002 \u9996\u5148\uff0c\u9876\u5c42\u7c7b\u4e0d\u80fd\u662f\u4e00\u4e2a\u5bc6\u5c01\u63a5\u53e3\uff0c\u5e94\u8be5\u662f\u4e00\u4e2a\u7c7b\u3002 \u5176\u6b21\uff0c\u6240\u6709\u5b50\u7c7b\u5747\u5e94\u5f53\u4f4d\u4e8e\u540c\u4e00\u6587\u4ef6\u4e2d\u3002<\/p>\n<p>Kotlin 1.5 \u53bb\u9664\u4e86\u8fd9\u4e24\u4e2a\u7ea6\u675f\uff1a\u60a8\u73b0\u5728\u53ef\u4ee5\u4f7f\u4e00\u4e2a\u63a5\u53e3\u5bc6\u5c01\u3002 \u5b50\u7c7b\uff08\u5305\u62ec\u5bc6\u5c01\u7c7b\u548c\u5bc6\u5c01\u63a5\u53e3\uff09\u5e94\u4e0e super \u7c7b\u4f4d\u4e8e\u540c\u4e00\u7f16\u8bd1\u5355\u5143\u548c\u540c\u4e00\u8f6f\u4ef6\u5305\u4e2d\uff0c\u4f46\u73b0\u5728\u53ef\u4ee5\u4f4d\u4e8e\u4e0d\u540c\u6587\u4ef6\u4e2d\u3002<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\nsealed interface Expr\r\ndata class Const(val number: Double) : Expr\r\ndata class Sum(val e1: Expr, val e2: Expr) : Expr\r\nobject NotANumber : Expr\r\n\r\nfun eval(expr: Expr): Double = when(expr) {\r\n    is Const -&gt; expr.number\r\n    is Sum -&gt; eval(expr.e1) + eval(expr.e2)\r\n    NotANumber -&gt; Double.NaN\r\n}\r\n<\/pre>\n<p>\u5bc6\u5c01\u7c7b\u4ee5\u53ca\u73b0\u5728\u7684\u5bc6\u5c01\u63a5\u53e3\u5bf9\u4e8e\u5b9a\u4e49\u62bd\u8c61\u6570\u636e\u7c7b\u578b (ADT) \u5c42\u6b21\u7ed3\u6784\u975e\u5e38\u5b9e\u7528\u3002<\/p>\n<p>\u4f7f\u7528\u5bc6\u5c01\u63a5\u53e3\u73b0\u5728\u8fd8\u80fd\u591f\u5f88\u597d\u5730\u89e3\u51b3\u4e86\u53e6\u4e00\u4e2a\u91cd\u8981\u4f7f\u7528\u573a\u666f\uff0c\u5373\u5173\u95ed\u4e00\u4e2a\u63a5\u53e3\u7684\u5e93\u5916\u7ee7\u627f\u4e0e\u5b9e\u73b0\u3002 \u5c06\u63a5\u53e3\u5b9a\u4e49\u4e3a\u5bc6\u5c01\u4f1a\u5c06\u5176\u5b9e\u73b0\u9650\u5236\u5230\u76f8\u540c\u7684\u7f16\u8bd1\u5355\u5143\u548c\u76f8\u540c\u7684\u8f6f\u4ef6\u5305\uff0c\u5bf9\u4e8e\u5e93\uff0c\u8fd9\u6837\u53ef\u4ee5\u7981\u6b62\u5e93\u5916\u5b9e\u73b0\u3002<\/p>\n<p>\u4f8b\u5982\uff0c<code>kotlinx.coroutines<\/code> \u8f6f\u4ef6\u5305\u4e2d\u7684 <code>Job<\/code> \u63a5\u53e3\u53ea\u80fd\u5728 <code>kotlinx.coroutines<\/code> \u5e93\u4e2d\u5b9e\u73b0\u3002 <code>sealed<\/code> \u540e\uff0c\u6b64\u610f\u56fe\u4f1a\u53d8\u6210\u663e\u5f0f\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\npackage kotlinx.coroutines\r\nsealed interface Job { ... }\r\n<\/pre>\n<p>\u4f5c\u4e3a\u5e93\u7684\u7528\u6237\uff0c\u60a8\u5c06\u65e0\u6cd5\u518d\u5b9a\u4e49\u81ea\u5df1\u7684 <code>Job<\/code> \u5b50\u7c7b\u3002 \u8fd9\u8fc7\u53bb\u4e00\u76f4\u662f\u201c\u9690\u542b\u7684\u201d\uff0c\u4f46\u662f\u4f7f\u7528\u5bc6\u5c01\u63a5\u53e3\u540e\uff0c\u7f16\u8bd1\u5668\u53ef\u4ee5\u6b63\u5f0f\u7981\u6b62\u3002<\/p>\n<h3>\u672a\u6765\u4f7f\u7528 JVM \u652f\u6301<\/h3>\n<p><a name = \"new-sealed-jvm-support\"><\/a><\/p>\n<p>Java 15 \u548c JVM \u4e2d\u5f15\u5165\u4e86\u5bf9\u5bc6\u5c01\u7c7b\u7684\u9884\u89c8\u652f\u6301\u3002 \u672a\u6765\uff0c\u5982\u679c\u60a8\u5c06 Kotlin \u4ee3\u7801\u7f16\u8bd1\u5230\u6700\u65b0\u7684 JVM\uff08\u5f88\u53ef\u80fd\u5230 JVM 17 \u6216\u66f4\u9ad8\u7248\u672c\u65f6\u6b64\u529f\u80fd\u4f1a\u7a33\u5b9a\u63d0\u4f9b\uff09\uff0c\u6211\u4eec\u5c06\u5bf9\u5bc6\u5c01\u7c7b\u4f7f\u7528\u81ea\u7136\u7684 JVM \u652f\u6301\u3002<\/p>\n<p>\u5728 Java \u4e2d\uff0c\u663e\u5f0f\u5217\u51fa\u7ed9\u5b9a\u5bc6\u5c01\u7c7b\u6216\u63a5\u53e3\u7684\u6240\u6709\u5b50\u7c7b\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\n\/\/ Java\r\npublic sealed interface Expression\r\n    permits Const, Sum, NotANumber { ... }\r\n<\/pre>\n<p>\u6b64\u4fe1\u606f\u4f7f\u7528\u65b0\u7684 <code>PermittedSubclasses<\/code> \u7279\u6027\u5b58\u50a8\u5728\u7c7b\u6587\u4ef6\u4e2d\u3002 JVM \u53ef\u5728\u8fd0\u884c\u65f6\u8bc6\u522b\u5bc6\u5c01\u7c7b\uff0c\u5e76\u9632\u6b62\u672a\u6388\u6743\u5b50\u7c7b\u7684\u6269\u5c55\u3002<\/p>\n<p>\u672a\u6765\uff0c\u5f53\u60a8\u5c06 Kotlin \u7f16\u8bd1\u5230\u6700\u65b0\u7684 JVM \u65f6\uff0c\u5c06\u4f7f\u7528\u8fd9\u79cd\u65b0\u7684 JVM \u5bf9\u5bc6\u5c01\u7c7b\u7684\u652f\u6301\u3002 \u5728\u540e\u53f0\uff0c\u7f16\u8bd1\u5668\u5c06\u5728\u5b57\u8282\u7801\u4e2d\u751f\u6210\u5141\u8bb8\u7684\u5b50\u7c7b\u5217\u8868\uff0c\u786e\u4fdd\u5b58\u5728 JVM \u652f\u6301\u548c\u989d\u5916\u8fd0\u884c\u65f6\u68c0\u67e5\u3002<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\n\/\/ for JVM 17 or later\r\nExpr::class.java.permittedSubclasses \/\/ [Const, Sum, NotANumber]\r\n<\/pre>\n<p>\u5728 Kotlin \u4e2d\uff0c\u60a8\u65e0\u9700\u6307\u5b9a\u5b50\u7c7b\u5217\u8868\uff01 \u7f16\u8bd1\u5668\u5c06\u6839\u636e\u540c\u4e00\u8f6f\u4ef6\u5305\u4e2d\u7684\u58f0\u660e\u5b50\u7c7b\u751f\u6210\u5217\u8868\u3002<\/p>\n<p>super \u7c7b\u6216\u63a5\u53e3\u7684\u5b50\u7c7b\u7684\u663e\u5f0f\u6307\u5b9a\u529f\u80fd\u53ef\u80fd\u4f1a\u5728\u4ee5\u540e\u4f5c\u4e3a\u53ef\u9009\u89c4\u8303\u6dfb\u52a0\u3002 \u76ee\u524d\u6211\u4eec\u8ba4\u4e3a\u6ca1\u6709\u5fc5\u8981\uff0c\u4f46\u6211\u4eec\u5f88\u4e50\u610f\u4e86\u89e3\u60a8\u7684\u7528\u4f8b\uff0c\u4ee5\u53ca\u60a8\u662f\u5426\u9700\u8981\u8fd9\u4e2a\u529f\u80fd\uff01<\/p>\n<p>\u8bf7\u6ce8\u610f\uff0c\u5bf9\u4e8e\u8f83\u65e9\u7684 JVM \u7248\u672c\uff0c\u7406\u8bba\u4e0a\u53ef\u4ee5\u4e3a Kotlin \u5bc6\u5c01\u63a5\u53e3\u5b9a\u4e49 Java \u5b50\u7c7b\uff0c\u4f46\u4e0d\u8981\u8fd9\u4e48\u505a\uff01 \u7531\u4e8e JVM \u5bf9\u5141\u8bb8\u7684\u5b50\u7c7b\u7684\u652f\u6301\u5c1a\u4e0d\u53ef\u7528\uff0c\u6240\u4ee5\u6b64\u7ea6\u675f\u53ea\u80fd\u7531 Kotlin \u7f16\u8bd1\u5668\u6267\u884c\u3002 \u6211\u4eec\u5c06\u6dfb\u52a0 IDE \u8b66\u544a\uff0c\u9632\u6b62\u610f\u5916\u6267\u884c\u6b64\u64cd\u4f5c\u3002 \u672a\u6765\uff0c\u65b0\u673a\u5236\u5c06\u7528\u4e8e\u6700\u65b0\u7684 JVM \u7248\u672c\uff0c\u786e\u4fdd\u6ca1\u6709\u6765\u81ea Java \u7684\u201c\u672a\u6388\u6743\u201d\u5b50\u7c7b\u3002<\/p>\n<p>\u60a8\u53ef\u4ee5\u5728\u76f8\u5e94\u7684 <a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/proposals\/jvm-records.md\" target=\"_blank\" rel=\"noopener\">KEEP<\/a>\u3001<a href=\"https:\/\/kotlinlang.org\/docs\/reference\/whatsnew1430.html#jvm-records-support\" target=\"_blank\" rel=\"noopener\">\u6587\u6863<\/a>\u548c\u6b64<a href=\"https:\/\/youtrack.jetbrains.com\/issue\/KT-42433\" target=\"_blank\" rel=\"noopener\">\u95ee\u9898<\/a>\u4e0b\u8ba8\u8bba\u4e2d\u9605\u8bfb\u6709\u5173\u5bc6\u5c01\u63a5\u53e3\u548c\u653e\u5bbd\u5bc6\u5c01\u7c7b\u9650\u5236\u7684\u66f4\u591a\u8be6\u7ec6\u4fe1\u606f\u3002<\/p>\n<h2>\u5982\u4f55\u8bd5\u7528\u65b0\u529f\u80fd<\/h2>\n<p><a name = \"how-to-try\"><\/a><\/p>\n<p>\u60a8\u9700\u8981\u4f7f\u7528 Kotlin 1.4.30\u3002 \u6307\u5b9a\u8bed\u8a00<a href=\"https:\/\/kotlinlang.org\/docs\/reference\/compiler-reference.html#-language-version-version\" target=\"_blank\" rel=\"noopener\">\u7248\u672c<\/a> 1.5 \u4ee5\u542f\u7528\u65b0\u529f\u80fd\uff1a<\/p>\n<pre class=\"kotlin-code\" data-highlight-only=\"true\" theme=\"idea\" indent=\"4\" style=\"visibility: hidden; padding: 36px 0;\">\r\ncompileKotlin {\r\n    kotlinOptions {\r\n        languageVersion = &quot;1.5&quot;\r\n        apiVersion = &quot;1.5&quot;\r\n    }\r\n}\r\n<\/pre>\n<p>\u8981\u8bd5\u7528 JVM \u8bb0\u5f55\uff0c\u8fd8\u9700\u8981\u4f7f\u7528 jvmTarget 15 \u5e76\u542f\u7528 JVM \u9884\u89c8\u529f\u80fd\uff1a\u6dfb\u52a0\u7f16\u8bd1\u5668\u9009\u9879 <code>-language-version 1.5<\/code> \u548c <code>-Xjvm-enable-preview<\/code>\u3002<\/p>\n<h3>\u9884\u53d1\u5e03\u8bf4\u660e<\/h3>\n<p>\u8bf7\u6ce8\u610f\uff0c\u5bf9\u65b0\u529f\u80fd\u7684\u652f\u6301\u4ecd\u4e3a\u5b9e\u9a8c\u6027\u8d28\uff0c\u5e76\u4e14 1.5 \u8bed\u8a00\u7248\u672c\u7684\u652f\u6301\u5904\u4e8e\u9884\u53d1\u5e03\u72b6\u6001\u3002 \u5728 Kotlin 1.4.30 \u7f16\u8bd1\u5668\u4e2d\u5c06\u8bed\u8a00\u7248\u672c\u8bbe\u7f6e\u4e3a 1.5 \u76f8\u5f53\u4e8e\u8bd5\u7528 1.5-M0 \u9884\u89c8\u7248\u3002 \u540e\u5411\u517c\u5bb9\u6027\u4fdd\u8bc1\u4e0d\u6db5\u76d6\u9884\u53d1\u5e03\u7248\u672c\u3002 \u529f\u80fd\u548c API \u5728\u540e\u7eed\u7248\u672c\u4e2d\u53ef\u80fd\u53d1\u751f\u53d8\u5316\u3002 \u5728\u6211\u4eec\u53d1\u5e03\u6700\u7ec8 Kotlin 1.5-RC \u65f6\uff0c\u9884\u53d1\u5e03\u7248\u672c\u4ea7\u751f\u7684\u6240\u6709\u4e8c\u8fdb\u5236\u6587\u4ef6\u90fd\u4f1a\u88ab\u7f16\u8bd1\u5668\u7981\u6b62\uff0c\u60a8\u9700\u8981\u91cd\u65b0\u7f16\u8bd1\u901a\u8fc7 1.5\u2011Mx \u7f16\u8bd1\u7684\u6240\u6709\u5185\u5bb9\u3002<\/p>\n<h3>\u5206\u4eab\u60a8\u7684\u53cd\u9988<\/h3>\n<p>\u8bf7\u6ce8\u610f\uff0c\u5bf9\u65b0\u529f\u80fd\u7684\u652f\u6301\u4ecd\u4e3a\u5b9e\u9a8c\u6027\u8d28\uff0c\u5e76\u4e14 1.5 \u8bed\u8a00\u7248\u672c\u7684\u652f\u6301\u5904\u4e8e\u9884\u53d1\u5e03\u72b6\u6001\u3002 \u5728 Kotlin 1.4.30 \u7f16\u8bd1\u5668\u4e2d\u5c06\u8bed\u8a00\u7248\u672c\u8bbe\u7f6e\u4e3a 1.5 \u76f8\u5f53\u4e8e\u8bd5\u7528 1.5-M0 \u9884\u89c8\u7248\u3002 \u540e\u5411\u517c\u5bb9\u6027\u4fdd\u8bc1\u4e0d\u6db5\u76d6\u9884\u53d1\u5e03\u7248\u672c\u3002 \u529f\u80fd\u548c API \u5728\u540e\u7eed\u7248\u672c\u4e2d\u53ef\u80fd\u53d1\u751f\u53d8\u5316\u3002 \u5728\u6211\u4eec\u53d1\u5e03\u6700\u7ec8 Kotlin 1.5-RC \u65f6\uff0c\u9884\u53d1\u5e03\u7248\u672c\u4ea7\u751f\u7684\u6240\u6709\u4e8c\u8fdb\u5236\u6587\u4ef6\u90fd\u4f1a\u88ab\u7f16\u8bd1\u5668\u7981\u6b62\uff0c\u60a8\u9700\u8981\u91cd\u65b0\u7f16\u8bd1\u901a\u8fc7 1.5\u2011Mx \u7f16\u8bd1\u7684\u6240\u6709\u5185\u5bb9\u3002<\/p>\n<p>\u5ef6\u4f38\u9605\u8bfb\u548c\u8ba8\u8bba\uff1a<\/p>\n<ul>\n<li><a href=\"https:\/\/kotlinlang.org\/docs\/reference\/whatsnew1430.html\" target=\"_blank\" rel=\"noopener\">\u201c\u6700\u65b0\u53d8\u5316\u201d\u6587\u6863\u9875<\/a>.<\/li>\n<li><a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/proposals\/inline-classes.md\" target=\"_blank\" rel=\"noopener\">\u5185\u8054\u7c7b KEEP<\/a>; \u8ba8\u8bba: <a href=\"https:\/\/youtrack.jetbrains.com\/issue\/KT-42434\" target=\"_blank\" rel=\"noopener\">KT-42434<\/a>.<\/li>\n<li><a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/notes\/value-classes.md\" target=\"_blank\" rel=\"noopener\">value \u7c7b\u8bbe\u8ba1\u6587\u6863<\/a>; \u8ba8\u8bba <a href=\"https:\/\/github.com\/Kotlin\/KEEP\/issues\/237\" target=\"_blank\" rel=\"noopener\">KEEP<\/a>.<\/li>\n<li><a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/proposals\/jvm-records.md\" target=\"_blank\" rel=\"noopener\">JVM \u8bb0\u5f55 KEEP<\/a>; \u8ba8\u8bba: <a href=\"https:\/\/youtrack.jetbrains.com\/issue\/KT-42430\" target=\"_blank\" rel=\"noopener\">KT-42430<\/a>.<\/li>\n<li><a href=\"https:\/\/github.com\/Kotlin\/KEEP\/blob\/master\/proposals\/sealed-interface-freedom.md\" target=\"_blank\" rel=\"noopener\">\u5bc6\u5c01\u63a5\u53e3\u548c\u5bc6\u5c01\u7c7b KEEP<\/a>; \u8ba8\u8bba: <a href=\"https:\/\/youtrack.jetbrains.com\/issue\/KT-42433\" target=\"_blank\" rel=\"noopener\">KT-42433<\/a>.<\/li>\n<\/ul>\n","protected":false},"author":814,"featured_media":0,"comment_status":"closed","ping_status":"closed","template":"","categories":[],"tags":[],"cross-post-tag":[],"acf":[],"_links":{"self":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/kotlin\/137389"}],"collection":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/kotlin"}],"about":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/types\/kotlin"}],"author":[{"embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/users\/814"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/comments?post=137389"}],"version-history":[{"count":3,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/kotlin\/137389\/revisions"}],"predecessor-version":[{"id":137399,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/kotlin\/137389\/revisions\/137399"}],"wp:attachment":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/media?parent=137389"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/categories?post=137389"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/tags?post=137389"},{"taxonomy":"cross-post-tag","embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/cross-post-tag?post=137389"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}