{"id":1254,"date":"2025-01-27T20:40:25","date_gmt":"2025-01-27T12:40:25","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=1254"},"modified":"2025-01-27T20:40:26","modified_gmt":"2025-01-27T12:40:26","slug":"%e6%8e%8c%e6%8f%a1java%e6%a0%b8%e5%bf%83%e7%b1%bb%e5%ba%93%ef%bc%9a%e5%ad%97%e7%ac%a6%e4%b8%b2%e3%80%81%e9%9b%86%e5%90%88%e3%80%81%e6%97%a5%e6%9c%9f%e4%b8%8ei-o%e6%93%8d%e4%bd%9c%e5%ae%8c%e5%85%a8","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/01\/27\/%e6%8e%8c%e6%8f%a1java%e6%a0%b8%e5%bf%83%e7%b1%bb%e5%ba%93%ef%bc%9a%e5%ad%97%e7%ac%a6%e4%b8%b2%e3%80%81%e9%9b%86%e5%90%88%e3%80%81%e6%97%a5%e6%9c%9f%e4%b8%8ei-o%e6%93%8d%e4%bd%9c%e5%ae%8c%e5%85%a8\/","title":{"rendered":"\u638c\u63e1Java\u6838\u5fc3\u7c7b\u5e93\uff1a\u5b57\u7b26\u4e32\u3001\u96c6\u5408\u3001\u65e5\u671f\u4e0eI\/O\u64cd\u4f5c\u5b8c\u5168\u6307\u5357"},"content":{"rendered":"\n

\u4e0b\u9762\u662f\u6838\u5fc3Java\u7c7b\u5e93<\/strong>\u7684\u8be6\u7ec6\u6559\u7a0b\uff0c\u6db5\u76d6\u4e86Java\u7684String\u7c7b\u3001\u96c6\u5408\u6846\u67b6\u3001\u65e5\u671f\u548c\u65f6\u95f4API\u3001I\/O\u64cd\u4f5c\u3001\u5f02\u5e38\u5904\u7406\u4ee5\u53caJava 8\u7684\u65b0\u7279\u6027\u7b49\u6838\u5fc3\u6982\u5ff5\u3002\u8fd9\u4e9b\u662f\u6bcf\u4e2aJava\u5f00\u53d1\u8005\u5fc5\u5907\u7684\u6280\u80fd\uff1a<\/p>\n\n\n\n

\n\n\n\n

Java\u6559\u7a0b\u4e4b\uff1a\u6838\u5fc3Java\u7c7b\u5e93<\/strong><\/h3>\n\n\n\n

1. String\u7c7b<\/strong><\/h4>\n\n\n\n
    \n
  • \u5b57\u7b26\u4e32\u7684\u521b\u5efa\u4e0e\u64cd\u4f5c<\/strong>
    Java\u4e2d\u7684String<\/code>\u7c7b\u7528\u4e8e\u5904\u7406\u5b57\u7b26\u4e32\uff0c\u5b57\u7b26\u4e32\u5728Java\u4e2d\u662f\u4e0d\u53ef\u53d8\u7684\u3002\u5b57\u7b26\u4e32\u53ef\u4ee5\u901a\u8fc7\u5b57\u9762\u91cf\u6216new<\/code>\u5173\u952e\u5b57\u521b\u5efa\u3002<\/li>\n<\/ul>\n\n\n\n
      String str1 = \"Hello\";\n  String str2 = new String(\"World\");\n  System.out.println(str1 + \" \" + str2);<\/code><\/pre>\n\n\n\n
    \u5e38\u7528\u64cd\u4f5c\u5305\u62ec\u5b57\u7b26\u4e32\u62fc\u63a5\u3001\u66ff\u6362\u3001\u67e5\u627e\u3001\u5927\u5c0f\u5199\u8f6c\u6362\u7b49\uff1a<\/p>\n\n\n\n
      String str = \"Hello World\";\n  String upperStr = str.toUpperCase();  \/\/ \u8f6c\u4e3a\u5927\u5199\n  String replacedStr = str.replace(\"World\", \"Java\");  \/\/ \u66ff\u6362\u5b57\u7b26\u4e32<\/code><\/pre>\n\n\n\n
      \n
    • StringBuffer\u4e0eStringBuilder<\/strong>
      StringBuffer<\/code>\u548cStringBuilder<\/code>\u90fd\u662f\u53ef\u53d8\u7684\u5b57\u7b26\u5e8f\u5217\uff0c\u4e3b\u8981\u7528\u4e8e\u5b57\u7b26\u4e32\u7684\u4fee\u6539\u64cd\u4f5c\u3002StringBuffer<\/code>\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff0c\u800cStringBuilder<\/code>\u4e0d\u662f\uff0c\u9002\u7528\u4e8e\u5355\u7ebf\u7a0b\u73af\u5883\u3002<\/li>\n<\/ul>\n\n\n\n
        StringBuffer sb = new StringBuffer(\"Hello\");\n  sb.append(\" World\");\n  System.out.println(sb);<\/code><\/pre>\n\n\n\n
      2. \u96c6\u5408\u6846\u67b6<\/strong><\/h4>\n\n\n\n
        \n
      • List\u3001Set\u3001Map\u7684\u63a5\u53e3\u53ca\u5176\u5b9e\u73b0\u7c7b<\/strong><\/li>\n\n\n\n
      • List<\/strong>\uff1a\u6709\u5e8f\u4e14\u53ef\u91cd\u590d\u7684\u96c6\u5408\uff0c\u5e38\u89c1\u5b9e\u73b0\u7c7b\u4e3aArrayList<\/code>\u3001LinkedList<\/code>\u3002
        java List<String> list = new ArrayList<>(); list.add(\"Java\"); list.add(\"Python\");<\/code><\/li>\n\n\n\n
      • Set<\/strong>\uff1a\u65e0\u5e8f\u4e14\u4e0d\u53ef\u91cd\u590d\u7684\u96c6\u5408\uff0c\u5e38\u89c1\u5b9e\u73b0\u7c7b\u4e3aHashSet<\/code>\u3001TreeSet<\/code>\u3002
        java Set<String> set = new HashSet<>(); set.add(\"Java\"); set.add(\"Java\");<\/code><\/li>\n\n\n\n
      • Map<\/strong>\uff1a\u5b58\u50a8\u952e\u503c\u5bf9\u7684\u96c6\u5408\uff0c\u5e38\u89c1\u5b9e\u73b0\u7c7b\u4e3aHashMap<\/code>\u3001TreeMap<\/code>\u3002 Map<String, Integer> map = new HashMap<>(); map.put(\"Java\", 1); map.put(\"Python\", 2);<\/code><\/li>\n\n\n\n
      • \u904d\u5386\u96c6\u5408<\/strong><\/li>\n\n\n\n
      • \u4f7f\u7528for-each<\/code>\u5faa\u73af\u904d\u5386\u96c6\u5408\uff1a
        “`java
        for (String s : list) {
        System.out.println(s);
        }<\/li>\n<\/ul>\n\n\n\n
        - **\u6cdb\u578b\u5728\u96c6\u5408\u4e2d\u7684\u4f7f\u7528**\n  \u6cdb\u578b\u53ef\u4ee5\u63d0\u4f9b\u7c7b\u578b\u5b89\u5168\u7684\u96c6\u5408\u64cd\u4f5c\uff0c\u907f\u514d\u7c7b\u578b\u8f6c\u6362\u9519\u8bef\u3002<\/code><\/pre>\n\n\n\n
        java
        List integerList = new ArrayList<>();
        integerList.add(1);
        integerList.add(2);<\/p>\n\n\n\n
        #### **3. \u65e5\u671f\u548c\u65f6\u95f4API**\n- **Date\u548cCalendar\u7c7b**\n  `Date`\u7c7b\u7528\u4e8e\u8868\u793a\u65e5\u671f\u548c\u65f6\u95f4\uff0c\u4f46\u5b83\u7684\u65b9\u6cd5\u5df2\u8fc7\u65f6\uff0c\u63a8\u8350\u4f7f\u7528`Calendar`\u7c7b\u3002<\/code><\/pre>\n\n\n\n
        java
        Date date = new Date();
        Calendar calendar = Calendar.getInstance();
        calendar.set(2023, Calendar.JANUARY, 1);<\/p>\n\n\n\n
        - **Java 8\u7684DateTime API**\n  Java 8\u5f15\u5165\u4e86`LocalDate`\u3001`LocalTime`\u3001`LocalDateTime`\u7b49\u7c7b\uff0c\u7b80\u5316\u4e86\u65e5\u671f\u548c\u65f6\u95f4\u7684\u5904\u7406\u3002<\/code><\/pre>\n\n\n\n
        java
        LocalDate date = LocalDate.now();
        LocalTime time = LocalTime.now();
        LocalDateTime dateTime = LocalDateTime.now();<\/p>\n\n\n\n
        #### **4. \u8f93\u5165\u8f93\u51fa\uff08I\/O\uff09**\n- **File\u7c7b**\n  `File`\u7c7b\u7528\u4e8e\u5904\u7406\u6587\u4ef6\u548c\u76ee\u5f55\u7684\u521b\u5efa\u3001\u5220\u9664\u3001\u91cd\u547d\u540d\u7b49\u64cd\u4f5c\u3002<\/code><\/pre>\n\n\n\n
        java
        File file = new File(“example.txt”);
        if (file.exists()) {
        System.out.println(“File exists.”);
        }<\/p>\n\n\n\n
        - **\u5b57\u8282\u6d41\u4e0e\u5b57\u7b26\u6d41**\n  - **\u5b57\u8282\u6d41**\uff1a\u7528\u4e8e\u5904\u7406\u6240\u6709\u7c7b\u578b\u7684\u6570\u636e\uff08\u5982\u56fe\u7247\u3001\u89c6\u9891\uff09\u3002\u5e38\u7528\u7c7b\u6709`InputStream`\u548c`OutputStream`\u3002\n  - **\u5b57\u7b26\u6d41**\uff1a\u7528\u4e8e\u5904\u7406\u6587\u672c\u6570\u636e\u3002\u5e38\u7528\u7c7b\u6709`Reader`\u548c`Writer`\u3002<\/code><\/pre>\n\n\n\n
        java
        FileInputStream fis = new FileInputStream(“file.txt”);
        FileOutputStream fos = new FileOutputStream(“output.txt”);<\/p>\n\n\n\n
        - **BufferedReader\u548cBufferedWriter**\n  `BufferedReader`\u7528\u4e8e\u9ad8\u6548\u5730\u8bfb\u53d6\u6587\u672c\uff0c`BufferedWriter`\u7528\u4e8e\u9ad8\u6548\u5730\u5199\u5165\u6587\u672c\u3002<\/code><\/pre>\n\n\n\n
        java
        BufferedReader reader = new BufferedReader(new FileReader(“input.txt”));
        BufferedWriter writer = new BufferedWriter(new FileWriter(“output.txt”));<\/p>\n\n\n\n
        - **\u5e8f\u5217\u5316\u4e0e\u53cd\u5e8f\u5217\u5316**\n  Java\u4e2d\u7684\u5e8f\u5217\u5316\u5c06\u5bf9\u8c61\u8f6c\u6362\u4e3a\u5b57\u8282\u6d41\u4ee5\u4fbf\u4fdd\u5b58\u6216\u4f20\u8f93\uff0c\u53cd\u5e8f\u5217\u5316\u5219\u662f\u5c06\u5b57\u8282\u6d41\u8f6c\u6362\u56de\u5bf9\u8c61\u3002<\/code><\/pre>\n\n\n\n
        java
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(“object.dat”));
        oos.writeObject(myObject);<\/p>\n\n\n\n
        #### **5. \u5f02\u5e38\u5904\u7406**\n- **\u5f02\u5e38\u7684\u79cd\u7c7b\uff08Checked\u5f02\u5e38\u548cUnchecked\u5f02\u5e38\uff09**\n  - **Checked\u5f02\u5e38**\uff1a\u7f16\u8bd1\u65f6\u5f02\u5e38\uff0c\u5982`IOException`\uff0c\u5fc5\u987b\u5904\u7406\u3002\n  - **Unchecked\u5f02\u5e38**\uff1a\u8fd0\u884c\u65f6\u5f02\u5e38\uff0c\u5982`NullPointerException`\uff0c\u4e0d\u9700\u8981\u5f3a\u5236\u5904\u7406\u3002\n\n- **try-catch-finally\u8bed\u53e5**\n  \u4f7f\u7528`try-catch`\u6765\u6355\u83b7\u5f02\u5e38\uff0c\u5e76\u5728`finally`\u4e2d\u6267\u884c\u6e05\u7406\u5de5\u4f5c\u3002<\/code><\/pre>\n\n\n\n
        java
        try {
        int result = 10 \/ 0;
        } catch (ArithmeticException e) {
        System.out.println(“Error: ” + e.getMessage());
        } finally {
        System.out.println(“Cleanup done.”);
        }<\/p>\n\n\n\n
        - **\u81ea\u5b9a\u4e49\u5f02\u5e38\u7c7b**\n  \u81ea\u5b9a\u4e49\u5f02\u5e38\u7c7b\u7ee7\u627f`Exception`\u7c7b\u6216\u5176\u5b50\u7c7b\u3002<\/code><\/pre>\n\n\n\n
        java
        public class CustomException extends Exception {
        public CustomException(String message) {
        super(message);
        }
        }<\/p>\n\n\n\n
        #### **6. Java 8\u65b0\u7279\u6027**\n- **Lambda\u8868\u8fbe\u5f0f**\n  Lambda\u8868\u8fbe\u5f0f\u7528\u4e8e\u7b80\u5316\u51fd\u6570\u5f0f\u7f16\u7a0b\uff0c\u5141\u8bb8\u4f20\u9012\u884c\u4e3a\uff08\u51fd\u6570\u4f5c\u4e3a\u53c2\u6570\uff09\u3002<\/code><\/pre>\n\n\n\n
        java
        List list = Arrays.asList(“Apple”, “Banana”, “Cherry”);
        list.forEach(s -> System.out.println(s));<\/p>\n\n\n\n
        - **Stream API**\n  Stream API\u7b80\u5316\u4e86\u5bf9\u96c6\u5408\u7684\u64cd\u4f5c\uff0c\u5982\u8fc7\u6ee4\u3001\u6392\u5e8f\u3001\u6620\u5c04\u7b49\u3002<\/code><\/pre>\n\n\n\n
        java
        list.stream().filter(s -> s.startsWith(“A”)).forEach(System.out::println);<\/p>\n\n\n\n
        - **Optional\u7c7b**\n  `Optional`\u7c7b\u7528\u4e8e\u907f\u514d`NullPointerException`\uff0c\u8868\u793a\u53ef\u80fd\u4e3anull\u7684\u503c\u3002<\/code><\/pre>\n\n\n\n
        java
        Optional optional = Optional.ofNullable(“Hello”);
        optional.ifPresent(System.out::println);<\/p>\n\n\n\n
        - **\u65b9\u6cd5\u5f15\u7528**\n  \u65b9\u6cd5\u5f15\u7528\u662fLambda\u8868\u8fbe\u5f0f\u7684\u4e00\u79cd\u7b80\u5316\u65b9\u5f0f\uff0c\u76f4\u63a5\u5f15\u7528\u5df2\u6709\u65b9\u6cd5\u3002<\/code><\/pre>\n\n\n\n
        java
        List list = Arrays.asList(“a”, “b”, “c”);
        list.forEach(System.out::println);
        “`<\/p>\n\n\n\n
        \n\n\n\n
        \u603b\u7ed3<\/strong><\/h3>\n\n\n\n
        \u672c\u90e8\u5206\u6db5\u76d6\u4e86Java\u6838\u5fc3\u7c7b\u5e93\u7684\u591a\u4e2a\u5173\u952e\u65b9\u9762\uff0c\u5305\u62ec\u5b57\u7b26\u4e32\u5904\u7406\u3001\u96c6\u5408\u6846\u67b6\u3001\u65e5\u671f\u65f6\u95f4API\u3001I\/O\u64cd\u4f5c\u3001\u5f02\u5e38\u5904\u7406\u53caJava 8\u7684\u65b0\u7279\u6027\u3002\u638c\u63e1\u8fd9\u4e9b\u7c7b\u5e93\u662fJava\u5f00\u53d1\u7684\u57fa\u7840\uff0c\u53ef\u4ee5\u5e2e\u52a9\u5f00\u53d1\u8005\u9ad8\u6548\u5730\u7f16\u5199\u3001\u7ba1\u7406\u548c\u4f18\u5316\u5e94\u7528\u7a0b\u5e8f\u3002\u65e0\u8bba\u662f\u57fa\u7840\u64cd\u4f5c\uff0c\u8fd8\u662f\u66f4\u590d\u6742\u7684\u529f\u80fd\uff0c\u90fd\u80fd\u901a\u8fc7\u8fd9\u4e9b\u7c7b\u5e93\u8f7b\u677e\u5b9e\u73b0\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
        \u4e0b\u9762\u662f\u6838\u5fc3Java\u7c7b\u5e93\u7684\u8be6\u7ec6\u6559\u7a0b\uff0c\u6db5\u76d6\u4e86Java\u7684String\u7c7b\u3001\u96c6\u5408\u6846\u67b6\u3001\u65e5\u671f\u548c\u65f6\u95f4API\u3001I\/O\u64cd\u4f5c\u3001\u5f02\u5e38 […]<\/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-1254","post","type-post","status-publish","format-standard","hentry","category-java"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/1254","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=1254"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/1254\/revisions"}],"predecessor-version":[{"id":1255,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/1254\/revisions\/1255"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=1254"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=1254"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=1254"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}