{"id":1576,"date":"2026-06-13T20:56:17","date_gmt":"2026-06-13T12:56:17","guid":{"rendered":"https:\/\/yunyanglib.cn\/?p=1576"},"modified":"2026-06-13T20:56:18","modified_gmt":"2026-06-13T12:56:18","slug":"%e3%80%90java%e3%80%91%e5%b8%b8%e7%94%a8%e5%b7%a5%e5%85%b7%e7%b1%bb-stringutils-%e5%85%a8%e6%96%b9%e4%bd%8d%e4%bd%bf%e7%94%a8%e6%80%bb%e7%bb%93","status":"publish","type":"post","link":"https:\/\/yunyanglib.cn\/?p=1576","title":{"rendered":"\u3010Java\u3011\u5e38\u7528\u5de5\u5177\u7c7b \u2014\u2014StringUtils \u5168\u65b9\u4f4d\u4f7f\u7528\u603b\u7ed3"},"content":{"rendered":"\n

\u5927\u5bb6\u597d\uff0c\u6211\u662f\u4e91\u626c\uff0c\u65e5\u5e38\u5f00\u53d1\u4e2d\u5904\u7406\u5b57\u7b26\u4e32\u662f\u5bb6\u5e38\u4fbf\u996d\uff0c\u539f\u751fString<\/code>\u81ea\u5e26\u7684\u65b9\u6cd5\u7ecf\u5e38\u8981\u505a\u975e\u7a7a\u5224\u65ad\u3001\u7a7a\u683c\u5904\u7406\u3001\u5206\u9694\u62fc\u63a5\uff0c\u5927\u91cf\u5197\u4f59 if \u4ee3\u7801\u5f88\u7e41\u7410\u3002Apache \u63d0\u4f9b\u7684org.apache.commons.lang3.StringUtils<\/code>\u5de5\u5177\u7c7b\u5c01\u88c5\u4e86\u9ad8\u9891\u5b57\u7b26\u4e32\u64cd\u4f5c\uff0c\u5927\u5e45\u7b80\u5316\u5f00\u53d1\uff0c\u4eca\u5929\u6574\u7406\u4e00\u4efd\u65e5\u5e38\u6700\u5b9e\u7528\u7684\u7528\u6cd5\uff0c\u9644\u5e26\u5b9e\u64cd\u4ee3\u7801\u3002<\/p>\n\n\n\n

\u4e00\u3001Maven \u4f9d\u8d56\u5f15\u5165<\/h2>\n\n\n\n

\u60f3\u8981\u4f7f\u7528StringUtils<\/code>\uff0c\u9996\u5148\u5728pom.xml<\/code>\u5bfc\u5165 commons-lang3 \u4f9d\u8d56\uff1a<\/p>\n\n\n\n

<!-- commons-lang3\u5de5\u5177\u5305 -->\n<dependency>\n    <groupId>org.apache.commons<\/groupId>\n    <artifactId>commons-lang3<\/artifactId>\n    <version>3.14.0<\/version>\n<\/dependency>\n<\/code><\/pre>\n\n\n\n
\n
\u6ce8\uff1a\u9879\u76ee\u6ca1\u6709 Maven \u7ba1\u7406\u7684\u8bdd\uff0c\u53ef\u624b\u52a8\u5bfc\u5165\u5bf9\u5e94 jar \u5305\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u4e8c\u3001\u5b57\u7b26\u4e32\u7a7a\u503c\u5224\u65ad\uff08\u5f00\u53d1\u6700\u9ad8\u9891\uff09<\/h2>\n\n\n\n
\u539f\u751fstr.isEmpty()<\/code>\u65e0\u6cd5\u8bc6\u522b\u5168\u7a7a\u683c\u5b57\u7b26\u4e32\u3001null \u7a7a\u6307\u9488\uff0cStringUtils<\/code>\u63d0\u4f9b\u56db\u7ec4\u5224\u7a7a\u65b9\u6cd5\uff0c\u533a\u5206\u7a7a\u767d\u5b57\u7b26<\/strong>\u548c\u7a7a\u5b57\u7b26\u4e32<\/strong>\uff1a<\/p>\n\n\n\n
    \n
  1. isEmpty()<\/code>\uff1anull \/ \u957f\u5ea6 0 \u2192 true\uff1b\u5168\u7a7a\u683c\u5b57\u7b26\u4e32\u2192false<\/li>\n\n\n\n
  2. isNotEmpty()<\/code>\uff1aisEmpty<\/code>\u53d6\u53cd<\/li>\n\n\n\n
  3. isBlank()<\/code>\uff1anull \/ \u7a7a\u4e32 \/ \u5168\u662f\u7a7a\u683c\u5236\u8868\u7b26 \u2192 true\uff08\u4e1a\u52a1\u53c2\u6570\u6821\u9a8c\u9996\u9009\uff09<\/li>\n\n\n\n
  4. isNotBlank()<\/code>\uff1aisBlank<\/code>\u53d6\u53cd<\/li>\n<\/ol>\n\n\n\n
    import org.apache.commons.lang3.StringUtils;\n\npublic class StringTest {\n    public static void main(String[] args) {\n        String str1 = null;\n        String str2 = \"\";\n        String str3 = \"   \";\n        String str4 = \"java\u5f00\u53d1\";\n\n        System.out.println(StringUtils.isEmpty(str1)); \/\/ true\n        System.out.println(StringUtils.isEmpty(str2)); \/\/ true\n        System.out.println(StringUtils.isEmpty(str3)); \/\/ false\n\n        System.out.println(StringUtils.isBlank(str1)); \/\/ true\n        System.out.println(StringUtils.isBlank(str2)); \/\/ true\n        System.out.println(StringUtils.isBlank(str3)); \/\/ true\n        System.out.println(StringUtils.isNotBlank(str4));\/\/ true\n    }\n}\n<\/code><\/pre>\n\n\n\n
    \n
    \u4e1a\u52a1\u5c0f\u6280\u5de7\uff1a\u8868\u5355\u5165\u53c2\u6821\u9a8c\u4f18\u5148\u7528isNotBlank<\/code>\uff0c\u907f\u514d\u7528\u6237\u8f93\u5165\u5168\u7a7a\u683c\u6570\u636e\u3002<\/p>\n<\/blockquote>\n\n\n\n
    \u4e09\u3001\u5b89\u5168\u5206\u9694\u5b57\u7b26\u4e32 split<\/h2>\n\n\n\n
    \u539f\u751fString.split()<\/code>\u9047\u5230\u7279\u6b8a\u5206\u9694\u7b26\u3001null \u5b57\u7b26\u4e32\u6781\u6613\u7a7a\u6307\u9488\uff0cStringUtils.split<\/code>\u505a\u4e86\u7a7a\u5b89\u5168\u5904\u7406\uff1a<\/p>\n\n\n\n
    public static void main(String[] args) {\n    String str = \"java,mysql,linux\";\n    String emptyStr = null;\n    \/\/ \u6309\u9017\u53f7\u5206\u5272\n    String[] arr = StringUtils.split(str, \",\");\n    for (String s : arr) {\n        System.out.print(s + \" \"); \/\/ java mysql linux\n    }\n    \/\/ null\u5165\u53c2\u4e0d\u4f1a\u62a5\u9519\uff0c\u8fd4\u56de\u7a7a\u6570\u7ec4\n    String[] arr2 = StringUtils.split(emptyStr, \",\");\n    System.out.println(Arrays.toString(arr2)); \/\/ null\n}\n<\/code><\/pre>\n\n\n\n
    \u56db\u3001\u5224\u65ad\u5b57\u7b26\u4e32\u662f\u5426\u7eaf\u6570\u5b57 isNumeric<\/h2>\n\n\n\n
    \u6821\u9a8c\u7f16\u53f7\u3001\u624b\u673a\u53f7\u7247\u6bb5\u7b49\u6570\u5b57\u573a\u666f\uff0c\u5feb\u901f\u5224\u65ad\u5b57\u7b26\u4e32\u662f\u5426\u5168\u90e8\u7531\u6570\u5b57\u7ec4\u6210\uff1a<\/p>\n\n\n\n
    public static void main(String[] args) {\n    String num1 = \"123456\";\n    String num2 = \"12a34\";\n    String num3 = \"-123\";\n    System.out.println(StringUtils.isNumeric(num1));\/\/true\n    System.out.println(StringUtils.isNumeric(num2));\/\/false\n    System.out.println(StringUtils.isNumeric(num3));\/\/false\uff08\u8d1f\u53f7\u4e0d\u7b97\u6570\u5b57\uff09\n}\n<\/code><\/pre>\n\n\n\n
    \u4e94\u3001\u96c6\u5408 \/ \u6570\u7ec4\u62fc\u63a5\u5b57\u7b26\u4e32 join<\/h2>\n\n\n\n
    \u65e5\u5e38\u5bfc\u51fa\u3001\u62fc\u63a5 ID \u9017\u53f7\u4e32\uff0c\u4e0d\u7528\u5faa\u73af\u62fc\u63a5\uff0cjoin<\/code>\u4e00\u952e\u641e\u5b9a\uff1a<\/p>\n\n\n\n
    import java.util.ArrayList;\nimport java.util.List;\n\npublic static void main(String[] args) {\n    List<String> list = new ArrayList<>();\n    list.add(\"SpringBoot\");\n    list.add(\"MyBatis\");\n    list.add(\"Redis\");\n    \/\/ \u4f7f\u7528\u9017\u53f7\u62fc\u63a5\u96c6\u5408\n    String joinStr = StringUtils.join(list, \",\");\n    System.out.println(joinStr); \/\/ SpringBoot,MyBatis,Redis\n}\n<\/code><\/pre>\n\n\n\n
    \u516d\u3001\u9996\u5c3e\u53bb\u7a7a\u683c\u7cfb\u5217 trim \u65b9\u6cd5<\/h2>\n\n\n\n
    \u65b9\u6cd5<\/th>\u4f5c\u7528<\/th><\/tr><\/thead>
    trim<\/td>\u53bb\u9996\u5c3e\u7a7a\u683c\uff0cnull \u8fd4\u56de null<\/td><\/tr>
    trimToEmpty<\/td>\u53bb\u9996\u5c3e\u7a7a\u683c\uff0cnull \u8fd4\u56de\u7a7a\u5b57\u7b26\u4e32 “”<\/td><\/tr>
    trimToNull<\/td>\u53bb\u9996\u5c3e\u7a7a\u683c\uff0c\u7a7a\u4e32 \/ \u5168\u7a7a\u683c\u8fd4\u56de null<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    public static void main(String[] args) {\n    String str = \"  \u4e91\u626c\u7f16\u7a0b  \";\n    System.out.println(StringUtils.trim(str)); \/\/\u4e91\u626c\u7f16\u7a0b\n    System.out.println(StringUtils.trimToEmpty(null));\/\/\u7a7a\u5b57\u7b26\u4e32\n    System.out.println(StringUtils.trimToNull(\"   \"));\/\/null\n}\n<\/code><\/pre>\n\n\n\n
    \u4e03\u3001\u5b57\u7b26\u4e32\u5bf9\u6bd4\u3001\u9996\u5c3e\u5339\u914d\u3001\u622a\u53d6\u66ff\u6362<\/h2>\n\n\n\n
    1. \u5b89\u5168 equals\uff08\u907f\u514d\u7a7a\u6307\u9488\uff09<\/h3>\n\n\n\n
    \/\/ \u4e0d\u7528\u5148\u5224null\uff0c\u76f4\u63a5\u5bf9\u6bd4\nSystem.out.println(StringUtils.equals(null, null));\/\/true\nSystem.out.println(StringUtils.equals(\"Java\", \"java\"));\/\/false\nSystem.out.println(StringUtils.equalsIgnoreCase(\"Java\", \"java\"));\/\/true\n<\/code><\/pre>\n\n\n\n
    2. \u9996\u5c3e\u5339\u914d\u3001\u5305\u542b\u5b57\u7b26<\/h3>\n\n\n\n
    String content = \"StringUtils\u5de5\u5177\u7c7b\";\nSystem.out.println(StringUtils.startsWith(content, \"String\"));\/\/true\nSystem.out.println(StringUtils.endsWith(content, \"\u5de5\u5177\u7c7b\"));\/\/true\nSystem.out.println(StringUtils.contains(content, \"\u5de5\u5177\"));\/\/true\n<\/code><\/pre>\n\n\n\n
    3. \u5b57\u7b26\u4e32\u66ff\u6362\u4e0e\u622a\u53d6<\/h3>\n\n\n\n
    String source = \"hello java\";\n\/\/\u666e\u901a\u66ff\u6362\nString replace = StringUtils.replace(source, \"java\", \"mysql\");\nSystem.out.println(replace); \/\/hello mysql\n\/\/\u6307\u5b9a\u4e0b\u6807\u622a\u53d6\nString sub = StringUtils.substring(source, 0, 5);\nSystem.out.println(sub);\/\/hello\n<\/code><\/pre>\n\n\n\n
    4. \u9996\u5b57\u6bcd\u5927\u5c0f\u5199\u8f6c\u6362<\/h3>\n\n\n\n
    String word = \"spring\";\nSystem.out.println(StringUtils.capitalize(word));\/\/Spring\nString word2 = \"Mysql\";\nSystem.out.println(StringUtils.uncapitalize(word2));\/\/mysql\n<\/code><\/pre>\n\n\n\n
    \u516b\u3001\u603b\u7ed3<\/h2>\n\n\n\n
    StringUtils<\/code>\u662f\u540e\u7aef\u5f00\u53d1\u5fc5\u5907\u5de5\u5177\u7c7b\uff0c\u6838\u5fc3\u4f18\u52bf\u5c31\u662f\u7a7a\u5b89\u5168<\/strong>\uff0c\u89c4\u907f\u5927\u91cfnull<\/code>\u5224\u65ad\u4ee3\u7801\u3002\u9664\u4e86\u6587\u4e2d\u793a\u4f8b\u65b9\u6cd5\uff0c\u8fd8\u6709indexOf<\/code>\u3001lastIndexOf<\/code>\u7b49\u67e5\u627e API\uff0c\u7528\u6cd5\u903b\u8f91\u4e00\u81f4\u3002\u540e\u7eed\u6211\u4f1a\u7ee7\u7eed\u66f4\u65b0 Java IO \u6d41\u3001MySQL \u5b9e\u64cd\u76f8\u5173\u535a\u6587\uff0c\u611f\u5174\u8da3\u53ef\u4ee5\u6301\u7eed\u5173\u6ce8\u6211\u7684\u535a\u5ba2\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
    \u5927\u5bb6\u597d\uff0c\u6211\u662f\u4e91\u626c\uff0c\u65e5\u5e38\u5f00\u53d1\u4e2d\u5904\u7406\u5b57\u7b26\u4e32\u662f\u5bb6\u5e38\u4fbf\u996d\uff0c\u539f\u751fString\u81ea\u5e26\u7684\u65b9\u6cd5\u7ecf\u5e38\u8981\u505a\u975e\u7a7a\u5224\u65ad\u3001\u7a7a\u683c\u5904\u7406\u3001\u5206\u9694\u62fc<\/p>\n
    \n\t\t\t\t Read More <\/span> <\/i><\/a>\n\t\t\t<\/div>\n","protected":false},"author":1,"featured_media":1577,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20],"tags":[15],"class_list":["post-1576","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-java","tag-java"],"_links":{"self":[{"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=\/wp\/v2\/posts\/1576","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1576"}],"version-history":[{"count":3,"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=\/wp\/v2\/posts\/1576\/revisions"}],"predecessor-version":[{"id":1580,"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=\/wp\/v2\/posts\/1576\/revisions\/1580"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=\/wp\/v2\/media\/1577"}],"wp:attachment":[{"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1576"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1576"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/yunyanglib.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1576"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}