添加 随机数生成

README.md

@@ -119,7 +119,7 @@ mvn package
 编译成功后，将 `target/gnu-java-utils-library-1.0.0.jar` 放入项目依赖中。</br>
 或者在releases中下载最新版jar包，放入项目依赖中。
 
-#### 使用示例
+#### 使用示例：
 
 **pom.xml**
 ```xml

src/main/java/top/gtb520/java/gnu/java/utils/library/main.java

@@ -1,6 +1,7 @@
 package top.gtb520.java.gnu.java.utils.library;
 
 import top.gtb520.java.gnu.java.utils.library.utils.print.ColorNameEnum;
+import top.gtb520.java.gnu.java.utils.library.utils.processing.random.defaults;
 
 public interface main {
     // 压缩包操作相关接口与方法
@@ -38,4 +39,11 @@ public interface main {
             top.gtb520.java.gnu.java.utils.library.utils.print.echo.ColorHexPrintln(Message, ColorCode);
         }
     }
+
+    // 随机数生成接口与方法
+    interface random {
+        static int defaule(int start_scope, int end_scope) {
+            return defaults.random(start_scope, end_scope);
+        }
+    }
 }

src/main/java/top/gtb520/java/gnu/java/utils/library/utils/processing/random/defaults.java

@@ -0,0 +1,25 @@
+package top.gtb520.java.gnu.java.utils.library.utils.processing.random;
+
+import java.util.concurrent.ThreadLocalRandom;
+
+public class defaults {
+    /**
+     * 根据输入的范围生成随机数
+     * @param start_scope 起始范围
+     * @param end_scope 结束范围
+     * @return 随机数
+     */
+    public static int random(int start_scope, int end_scope) {
+        int random_double;
+
+        // 处理边界，确保起始范围小于等于结束范围
+        if (start_scope > end_scope) {
+            System.out.println("起始范围不能大于结束范围");
+            throw new IllegalArgumentException("起始范围不能大于结束范围");
+        }
+        // 生成随机数
+        random_double = ThreadLocalRandom.current().nextInt(start_scope, end_scope + 1);
+
+        return random_double;
+    }
+}

src/test/java/top/gtb520/java/gnu/java/utils/library/utils/processing/random/Test.java

@@ -0,0 +1,47 @@
+package top.gtb520.java.gnu.java.utils.library.utils.processing.random;
+
+import top.gtb520.java.gnu.java.utils.library.main;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadLocalRandom;
+
+// 毫无意义的随机数测试代码，在循环中执行随机数生成 10 亿次
+public class Test {
+    public static void main(String[] args) {
+        int totalTasks = 1_000_000_000;
+        // 根据CPU核心数创建固定大小的线程池，避免创建过多线程导致上下文切换开销
+        int threadCount = Runtime.getRuntime().availableProcessors();
+        ExecutorService executor = Executors.newFixedThreadPool(threadCount);
+
+        // 将总任务量平均分配给每个线程
+        int tasksPerThread = totalTasks / threadCount;
+
+        for (int t = 0; t < threadCount; t++) {
+            final int start = t * tasksPerThread;
+            // 处理余数，确保最后一个线程承担剩余任务
+            final int end = (t == threadCount - 1) ? totalTasks : start + tasksPerThread;
+
+            executor.submit(() -> {
+                // 【核心优化1】使用 ThreadLocalRandom 替代共享 Random
+                // 每个线程拥有独立的 seed，完全无锁，避免高并发下的 CAS 竞争
+                ThreadLocalRandom random = ThreadLocalRandom.current();
+
+                // 【核心优化2】将 I/O 与计算分离
+                // 在实际业务中，应只返回计算结果，而不是在循环中打印
+                for (int i = start; i < end; i++) {
+                    int random_i = random.nextInt(1, 1000000001); // [1, 1000000000]
+
+                    // 如果确实需要输出，建议降低频率（例如每1000万次输出一次）
+//                    if (i % 10000 == 0) {
+//                        System.out.println("随机数: " + random_i + " 当前循环位置: " + i);
+//                    }
+                    System.out.println("随机数: " + random_i + " 当前循环位置: " + i);
+                }
+            });
+        }
+
+        // 优雅关闭线程池
+        executor.shutdown();
+    }
+}

src/test/java/top/gtb520/java/gnu/java/utils/library/utils/processing/random/defauleTest.java

@@ -0,0 +1,142 @@
+package top.gtb520.java.gnu.java.utils.library.utils.processing.random;
+
+public class defauleTest {
+
+    static int passed = 0;
+    static int failed = 0;
+
+    public static void main(String[] args) {
+        System.out.println("========== defaults.random 测试开始 ==========");
+
+        testRandomInRange();
+        testRandomSameStartAndEnd();
+        testRandomNegativeRange();
+        testRandomReversedRange();
+        testRandomLargeRange();
+        testRandomDistribution();
+
+        System.out.println("========================================");
+        System.out.println("测试完成: 通过 " + passed + ", 失败 " + failed);
+        if (failed > 0) {
+            System.exit(1);
+        }
+    }
+
+    /**
+     * 测试正常范围内的随机数
+     */
+    static void testRandomInRange() {
+        String testName = "testRandomInRange";
+        try {
+            for (int i = 0; i < 100; i++) {
+                int result = defaults.random(1, 10);
+                if (result < 1 || result > 10) {
+                    assertCondition(testName + " - 随机数应在[1,10]范围内，实际: " + result, false);
+                    return;
+                }
+            }
+            assertCondition(testName + " - 100次随机数均在[1,10]范围内", true);
+        } catch (Exception e) {
+            assertCondition(testName + " - 不应抛出异常: " + e.getMessage(), false);
+        }
+    }
+
+    /**
+     * 测试起始值等于结束值
+     */
+    static void testRandomSameStartAndEnd() {
+        String testName = "testRandomSameStartAndEnd";
+        try {
+            int result = defaults.random(5, 5);
+            assertCondition(testName + " - 结果应等于5，实际: " + result, result == 5);
+        } catch (Exception e) {
+            assertCondition(testName + " - 不应抛出异常: " + e.getMessage(), false);
+        }
+    }
+
+    /**
+     * 测试负数范围
+     */
+    static void testRandomNegativeRange() {
+        String testName = "testRandomNegativeRange";
+        try {
+            for (int i = 0; i < 100; i++) {
+                int result = defaults.random(-10, -1);
+                if (result < -10 || result > -1) {
+                    assertCondition(testName + " - 随机数应在[-10,-1]范围内，实际: " + result, false);
+                    return;
+                }
+            }
+            assertCondition(testName + " - 100次随机数均在[-10,-1]范围内", true);
+        } catch (Exception e) {
+            assertCondition(testName + " - 不应抛出异常: " + e.getMessage(), false);
+        }
+    }
+
+    /**
+     * 测试起始值大于结束值应抛出异常
+     */
+    static void testRandomReversedRange() {
+        String testName = "testRandomReversedRange";
+        try {
+            defaults.random(10, 1);
+            assertCondition(testName + " - 应抛出IllegalArgumentException", false);
+        } catch (IllegalArgumentException e) {
+            assertCondition(testName + " - 应抛出IllegalArgumentException", true);
+        } catch (Exception e) {
+            assertCondition(testName + " - 异常类型不正确: " + e.getClass().getName(), false);
+        }
+    }
+
+    /**
+     * 测试大范围随机数
+     */
+    static void testRandomLargeRange() {
+        String testName = "testRandomLargeRange";
+        try {
+            for (int i = 0; i < 100; i++) {
+                int result = defaults.random(-1000000, 1000000);
+                if (result < -1000000 || result > 1000000) {
+                    assertCondition(testName + " - 随机数超出范围，实际: " + result, false);
+                    return;
+                }
+            }
+            assertCondition(testName + " - 100次随机数均在[-1000000,1000000]范围内", true);
+        } catch (Exception e) {
+            assertCondition(testName + " - 不应抛出异常: " + e.getMessage(), false);
+        }
+    }
+
+    /**
+     * 测试随机数分布（验证不会总是返回同一个值）
+     */
+    static void testRandomDistribution() {
+        String testName = "testRandomDistribution";
+        try {
+            int first = defaults.random(1, 1000000);
+            boolean hasDifferent = false;
+            for (int i = 0; i < 100; i++) {
+                int result = defaults.random(1, 1000000);
+                if (result != first) {
+                    hasDifferent = true;
+                    break;
+                }
+            }
+            assertCondition(testName + " - 100次调用应产生不同随机数", hasDifferent);
+        } catch (Exception e) {
+            assertCondition(testName + " - 不应抛出异常: " + e.getMessage(), false);
+        }
+    }
+
+    // ========== 辅助方法 ==========
+
+    static void assertCondition(String message, boolean condition) {
+        if (condition) {
+            System.out.println("[PASS] " + message);
+            passed++;
+        } else {
+            System.out.println("[FAIL] " + message);
+            failed++;
+        }
+    }
+}