{"id":2185,"date":"2025-03-01T18:22:54","date_gmt":"2025-03-01T10:22:54","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=2185"},"modified":"2025-03-01T18:33:40","modified_gmt":"2025-03-01T10:33:40","slug":"java-%e5%9f%ba%e6%9c%ac%e6%95%b0%e6%8d%ae%e7%b1%bb%e5%9e%8b","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/03\/01\/java-%e5%9f%ba%e6%9c%ac%e6%95%b0%e6%8d%ae%e7%b1%bb%e5%9e%8b\/","title":{"rendered":"Java \u57fa\u672c\u6570\u636e\u7c7b\u578b"},"content":{"rendered":"\n<p>\u5728 Java \u4e2d\uff0c<strong>\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/strong>\uff08Primitive Data Types\uff09\u662f\u6700\u57fa\u672c\u7684\u7c7b\u578b\uff0c\u5b83\u4eec\u4e0d\u662f\u5bf9\u8c61\uff0c\u76f4\u63a5\u5b58\u50a8\u503c\u3002Java \u63d0\u4f9b\u4e86 8 \u79cd\u57fa\u672c\u6570\u636e\u7c7b\u578b\uff0c\u6bcf\u79cd\u6570\u636e\u7c7b\u578b\u90fd\u6709\u5176\u56fa\u5b9a\u7684\u5927\u5c0f\u548c\u8303\u56f4\u3002\u5b83\u4eec\u7528\u4e8e\u5b58\u50a8\u4e0d\u540c\u7c7b\u578b\u7684\u6570\u636e\uff0c\u5982\u6574\u6570\u3001\u6d6e\u70b9\u6570\u3001\u5b57\u7b26\u548c\u5e03\u5c14\u503c\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e00\u3001Java \u4e2d\u7684 8 \u79cd\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">1\u3001<strong>byte<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>byte<\/code> \u662f\u6700\u5c0f\u7684\u6574\u6570\u7c7b\u578b\uff0c\u5360\u7528 1 \u4e2a\u5b57\u8282\uff088 \u4f4d\uff09\u3002\u5b83\u9002\u7528\u4e8e\u8282\u7701\u5185\u5b58\u7684\u573a\u666f\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a-128 \u5230 127\uff08\u5305\u542b\uff09<\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a0<\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java byte a = 100; byte b = -50;<\/code><\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">2\u3001<strong>short<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>short<\/code> \u662f\u6bd4 <code>byte<\/code> \u5927\u7684\u6574\u6570\u7c7b\u578b\uff0c\u5360\u7528 2 \u4e2a\u5b57\u8282\uff0816 \u4f4d\uff09\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a-32,768 \u5230 32,767\uff08\u5305\u542b\uff09<\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a0<\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java short s = 10000;<\/code><\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">3\u3001<strong>int<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>int<\/code> \u662f\u5e38\u7528\u7684\u6574\u6570\u7c7b\u578b\uff0c\u5360\u7528 4 \u4e2a\u5b57\u8282\uff0832 \u4f4d\uff09\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a-2^31 \u5230 2^31 &#8211; 1\uff0c\u5373 -2,147,483,648 \u5230 2,147,483,647<\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a0<\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java int num = 100000;<\/code><\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">4\u3001<strong>long<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>long<\/code> \u662f\u6bd4 <code>int<\/code> \u66f4\u5927\u7684\u6574\u6570\u7c7b\u578b\uff0c\u5360\u7528 8 \u4e2a\u5b57\u8282\uff0864 \u4f4d\uff09\u3002\u9002\u7528\u4e8e\u9700\u8981\u5b58\u50a8\u975e\u5e38\u5927\u6574\u6570\u7684\u60c5\u51b5\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a-2^63 \u5230 2^63 &#8211; 1\uff0c\u5373 -9,223,372,036,854,775,808 \u5230 9,223,372,036,854,775,807<\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a0L<\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java long bigNumber = 123456789012345L;<\/code><\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">5\u3001<strong>float<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>float<\/code> \u662f\u5355\u7cbe\u5ea6\u6d6e\u70b9\u6570\u7c7b\u578b\uff0c\u5360\u7528 4 \u4e2a\u5b57\u8282\uff0832 \u4f4d\uff09\u3002\u7528\u4e8e\u5b58\u50a8\u5c0f\u6570\uff0c\u7cbe\u5ea6\u8f83\u4f4e\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a\u7ea6 \u00b13.40282347E+38F\uff08\u6709\u6548\u4f4d\u6570\u4e3a 6~7 \u4f4d\u5341\u8fdb\u5236\u6570\uff09<\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a0.0f<\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java float pi = 3.14f;<\/code><\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">6\u3001<strong>double<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>double<\/code> \u662f\u53cc\u7cbe\u5ea6\u6d6e\u70b9\u6570\u7c7b\u578b\uff0c\u5360\u7528 8 \u4e2a\u5b57\u8282\uff0864 \u4f4d\uff09\u3002\u7528\u4e8e\u5b58\u50a8\u66f4\u7cbe\u786e\u7684\u5c0f\u6570\uff0c\u5e38\u7528\u4e8e\u79d1\u5b66\u8ba1\u7b97\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a\u7ea6 \u00b11.79769313486231570E+308\uff08\u6709\u6548\u4f4d\u6570\u4e3a 15~16 \u4f4d\u5341\u8fdb\u5236\u6570\uff09<\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a0.0d<\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java double pi = 3.141592653589793;<\/code><\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">7\u3001<strong>char<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>char<\/code> \u7528\u4e8e\u5b58\u50a8\u5355\u4e2a\u5b57\u7b26\uff0c\u5360\u7528 2 \u4e2a\u5b57\u8282\uff0816 \u4f4d\uff09\uff0c\u5e76\u4e14\u662f\u57fa\u4e8e Unicode \u7f16\u7801\u7684\u3002\u53ef\u4ee5\u5b58\u50a8\u51e0\u4e4e\u6240\u6709\u7684\u5b57\u7b26\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a0 \u5230 65,535\uff08\u5b57\u7b26\u7684 Unicode \u7f16\u7801\uff09<\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a&#8217;\\u0000&#8217;\uff08Unicode \u503c\u4e3a 0\uff09<\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java char letter = 'A'; char symbol = '$';<\/code><\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">8\u3001<strong>boolean<\/strong><\/h4>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63cf\u8ff0<\/strong>\uff1a<code>boolean<\/code> \u7528\u4e8e\u5b58\u50a8\u5e03\u5c14\u503c\uff0c\u8868\u793a <code>true<\/code> \u6216 <code>false<\/code>\uff0c\u901a\u5e38\u7528\u4e8e\u6761\u4ef6\u5224\u65ad\u3002<\/li>\n\n\n\n<li><strong>\u53d6\u503c\u8303\u56f4<\/strong>\uff1a<code>true<\/code> \u6216 <code>false<\/code><\/li>\n\n\n\n<li><strong>\u9ed8\u8ba4\u503c<\/strong>\uff1a<code>false<\/code><\/li>\n\n\n\n<li><strong>\u793a\u4f8b<\/strong>\uff1a<br><code>java boolean isJavaFun = true; boolean isJavaEasy = false;<\/code><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e8c\u3001<strong>\u57fa\u672c\u6570\u636e\u7c7b\u578b\u7684\u7279\u70b9<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u6574\u6570\u7c7b\u578b<\/strong>\uff1a<code>byte<\/code>\u3001<code>short<\/code>\u3001<code>int<\/code>\u3001<code>long<\/code>\uff0c\u7528\u4e8e\u5b58\u50a8\u6ca1\u6709\u5c0f\u6570\u7684\u6570\u503c\u3002<\/li>\n\n\n\n<li><strong>\u6d6e\u70b9\u7c7b\u578b<\/strong>\uff1a<code>float<\/code>\u3001<code>double<\/code>\uff0c\u7528\u4e8e\u5b58\u50a8\u5e26\u6709\u5c0f\u6570\u7684\u6570\u503c\u3002<code>float<\/code> \u7cbe\u5ea6\u8f83\u4f4e\uff0c<code>double<\/code> \u7cbe\u5ea6\u8f83\u9ad8\u3002<\/li>\n\n\n\n<li><strong>\u5b57\u7b26\u7c7b\u578b<\/strong>\uff1a<code>char<\/code>\uff0c\u7528\u4e8e\u5b58\u50a8\u5355\u4e2a\u5b57\u7b26\u3002<\/li>\n\n\n\n<li><strong>\u5e03\u5c14\u7c7b\u578b<\/strong>\uff1a<code>boolean<\/code>\uff0c\u7528\u4e8e\u8868\u793a\u903b\u8f91\u503c <code>true<\/code> \u6216 <code>false<\/code>\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e09\u3001<strong>\u6570\u636e\u7c7b\u578b\u7684\u9009\u62e9<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5185\u5b58\u6d88\u8017<\/strong>\uff1a<code>byte<\/code> \u548c <code>short<\/code> \u5360\u7528\u7684\u5185\u5b58\u8f83\u5c11\uff0c\u9002\u5408\u5904\u7406\u5c0f\u8303\u56f4\u7684\u6574\u6570\uff1b<code>int<\/code> \u548c <code>long<\/code> \u9002\u5408\u5927\u8303\u56f4\u7684\u6574\u6570\uff1b<code>float<\/code> \u548c <code>double<\/code> \u7528\u4e8e\u5b58\u50a8\u5c0f\u6570\uff0c<code>double<\/code> \u66f4\u4e3a\u7cbe\u786e\u3002<\/li>\n\n\n\n<li><strong>\u6027\u80fd<\/strong>\uff1a\u4e00\u822c\u60c5\u51b5\u4e0b\uff0c<code>int<\/code> \u548c <code>long<\/code> \u6027\u80fd\u8f83\u597d\uff0c<code>double<\/code> \u548c <code>float<\/code> \u5728\u6d89\u53ca\u5927\u91cf\u5c0f\u6570\u8ba1\u7b97\u65f6\u4f7f\u7528\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u56db\u3001<strong>\u81ea\u52a8\u7c7b\u578b\u8f6c\u6362\u548c\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362<\/strong><\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u81ea\u52a8\u7c7b\u578b\u8f6c\u6362\uff08\u9690\u5f0f\u7c7b\u578b\u8f6c\u6362\uff09<\/strong>\uff1a\u5f53\u4f60\u5c06\u4e00\u4e2a\u8f83\u5c0f\u8303\u56f4\u7684\u7c7b\u578b\u8d4b\u7ed9\u8f83\u5927\u8303\u56f4\u7684\u7c7b\u578b\u65f6\uff0cJava \u4f1a\u81ea\u52a8\u8fdb\u884c\u8f6c\u6362\u3002\u4f8b\u5982\uff0c<code>int<\/code> \u53ef\u4ee5\u81ea\u52a8\u8f6c\u6362\u4e3a <code>long<\/code>\uff0c<code>float<\/code> \u53ef\u4ee5\u81ea\u52a8\u8f6c\u6362\u4e3a <code>double<\/code>\u3002<\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>   int a = 10;\n   long b = a;  \/\/ \u81ea\u52a8\u5c06 int \u8f6c\u4e3a long<\/code><\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362\uff08\u663e\u5f0f\u7c7b\u578b\u8f6c\u6362\uff09<\/strong>\uff1a\u5f53\u4f60\u5c06\u4e00\u4e2a\u8f83\u5927\u8303\u56f4\u7684\u7c7b\u578b\u8d4b\u7ed9\u8f83\u5c0f\u8303\u56f4\u7684\u7c7b\u578b\u65f6\uff0c\u9700\u8981\u4f7f\u7528\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362\u6765\u907f\u514d\u6570\u636e\u4e22\u5931\u3002<\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>   double pi = 3.14159;\n   int intPi = (int) pi;  \/\/ \u5f3a\u5236\u7c7b\u578b\u8f6c\u6362\uff0c\u7ed3\u679c\u662f 3\uff0c\u4e22\u5931\u5c0f\u6570\u90e8\u5206<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e94\u3001<strong>\u603b\u7ed3<\/strong><\/h3>\n\n\n\n<p>Java \u7684\u57fa\u672c\u6570\u636e\u7c7b\u578b\u63d0\u4f9b\u4e86\u9ad8\u6548\u4e14\u57fa\u7840\u7684\u5b58\u50a8\u529f\u80fd\uff0c\u9002\u7528\u4e8e\u5404\u79cd\u8ba1\u7b97\u4efb\u52a1\u3002\u7406\u89e3\u6bcf\u79cd\u7c7b\u578b\u7684\u7279\u70b9\u3001\u8303\u56f4\u3001\u5b58\u50a8\u9700\u6c42\u4ee5\u53ca\u5982\u4f55\u8fdb\u884c\u7c7b\u578b\u8f6c\u6362\u662f Java \u7f16\u7a0b\u7684\u57fa\u7840\u3002\u66f4\u591a\u8be6\u7ec6\u5185\u5bb9\u8bf7\u5173\u6ce8\u5176\u4ed6\u76f8\u5173\u6587\u7ae0\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5728 Java \u4e2d\uff0c\u57fa\u672c\u6570\u636e\u7c7b\u578b\uff08Primitive Data Types\uff09\u662f\u6700\u57fa\u672c\u7684\u7c7b\u578b\uff0c\u5b83\u4eec\u4e0d\u662f\u5bf9\u8c61\uff0c\u76f4\u63a5\u5b58 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[68],"tags":[],"class_list":["post-2185","post","type-post","status-publish","format-standard","hentry","category-java"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2185","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=2185"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2185\/revisions"}],"predecessor-version":[{"id":2186,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/2185\/revisions\/2186"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=2185"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=2185"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=2185"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}