Java assert 关键字

示例

使用 assert 语句来测试表达式的真值:

public class Main {
  public static void main(String[] args) {
    // 启用断言
    ClassLoader loader = ClassLoader.getSystemClassLoader();
    loader.setDefaultAssertionStatus(true);
    
    // 运行断言示例
    AssertExample example = new AssertExample();
    example.run();
  }
}

class AssertExample {
  public void run() {
    int a = 12;
    try {
      assert a == 12; // Assertion without a fail message
      assert a == 12 : "a is not 12";
      assert a == 15 : "a is not 15";
    } catch (AssertionError e) {
      System.out.println(e.getMessage());
    }
  }
}

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