java - 如何使用 Lucene TestUtil 生成随机 Unicode 字符串

Question

我正在编写一些用于生成随机 Unicode 字符串的代码。我尝试使用 Lucene Test Utils 我的代码生成随机 Unicode 字符串如下

    for (int i = 0; i < 5000; i++) {
        Random random = new Random();
        final String s = TestUtil.randomUnicodeString(random, 12);
        //final String s = TestUtil.randomUnicodeString(random);Tried both
        final byte[] utf8 = new byte[s.length() * UnicodeUtil.MAX_UTF8_BYTES_PER_CHAR];
        final int utf8Len = UnicodeUtil.UTF16toUTF8(s, 0, s.length(), utf8);
        if(utf8Len !=8)
        {
            System.out.println("$$$$");
        }
    }

所以我检查了 Lucene 版本 6.2.0 的 lucene 代码中 randomUnicodeString 的实现

public static String randomUnicodeString(Random r, int maxLength) {
final int end = nextInt(r, 0, maxLength);
if (end == 0) {
  // allow 0 length
  return "";
}
final char[] buffer = new char[end];
randomFixedLengthUnicodeString(r, buffer, 0, buffer.length);
return new String(buffer, 0, end);

}

randomFixedLengthUnicodeString 的后续代码是

 public static void randomFixedLengthUnicodeString(Random random, char[] chars, int offset, int length) {
int i = offset;
final int end = offset + length;
while(i < end) {
  final int t = random.nextInt(5);
  if (0 == t && i < length - 1) {
    // Make a surrogate pair
    // High surrogate
    chars[i++] = (char) nextInt(random, 0xd800, 0xdbff);
    // Low surrogate
    chars[i++] = (char) nextInt(random, 0xdc00, 0xdfff);
  } else if (t <= 1) {
    chars[i++] = (char) random.nextInt(0x80);
  } else if (2 == t) {
    chars[i++] = (char) nextInt(random, 0x80, 0x7ff);
  } else if (3 == t) {
    chars[i++] = (char) nextInt(random, 0x800, 0xd7ff);
  } else if (4 == t) {
    chars[i++] = (char) nextInt(random, 0xe000, 0xffff);
  }
}

}

那么我收到异常的原因可能是什么

Exception in thread "main" java.lang.NoClassDefFoundError: com/carrotsearch/randomizedtesting/generators/RandomInts
at org.apache.lucene.util.TestUtil.nextInt(TestUtil.java:433)
at org.apache.lucene.util.TestUtil.randomUnicodeString(TestUtil.java:505)
at luceneLab.lab.main(lab.java:33)Caused by: java.lang.ClassNotFoundException: com.carrotsearch.randomizedtesting.generators.RandomInts
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 3 more

我是否为生成随机字符串的方法传递了错误的参数或我缺少的一些相互依赖关系？ 提前致谢。

Answer 1

正如异常所说，您的项目中缺少 com/carrotsearch/randomizedtesting/generators/RandomInts 。看起来 TestUtil 使用 com.carrotsearch.randomizedtesting ，因此您需要将其作为依赖项添加到您的项目中。