我正在尝试使用这里提到的Java基准测试:
https://www.ibm.com/developerworks/java/library/j-benchmark2/
可以在此处下载:
http://www.ellipticgroup.com/html/benchmarkingArticle.html
我尝试使用上述文章中的基本示例:
似乎任何对基准测试的调用最终都会使用StringUtil中的以下方法。
import bb.util.Benchmark;
public class ShortIndexesLoop {
public static void main(String[] args) throws Exception {
Callable<Integer> task =
new Callable<Integer>() { public Integer call() { return fibonacci(35); } };
System.out.println("fibonacci(35): " + new Benchmark(task));
}
protected static int fibonacci(int n) throws IllegalArgumentException {
if (n < 0) throw new IllegalArgumentException("n = " + n + " < 0");
if (n <= 1) return n;
return fibonacci(n - 1) + fibonacci(n - 2);
}
}
但是每次运行这个基准测试时,它都会在运行基准测试之前出现异常。
2015年6月13日下午1:45:37 StringUtil警告:字符串的行为与预期不符,请查看原因。
java.lang.Exception: substring does NOT share the same underlying char[] with its parent String
at bb.util.StringUtil.inspectStringConstructor(StringUtil.java:84)
at bb.util.StringUtil.<clinit>(StringUtil.java:75)
at bb.io.ConsoleUtil.<clinit>(ConsoleUtil.java:81)
at bb.util.Benchmark.sendUserMsg(Benchmark.java:1002)
at bb.util.Benchmark.osSpecificPreparation(Benchmark.java:579)
at bb.util.Benchmark.perform(Benchmark.java:541)
at bb.util.Benchmark.<init>(Benchmark.java:464)
at bb.util.Benchmark.<init>(Benchmark.java:439)
at ShortIndexesLoop.main(fib.java:13)
似乎任何对基准测试的调用最终都会使用StringUtil中的以下方法。
private static final boolean stringContructorTrimsGarbage = inspectStringConstructor();
private static boolean inspectStringConstructor() {
try {
// first prove that substring shares the same underlying char[] as the parent String:
String s1 = "abc123def";
String s2 = s1.substring(3, 6);
char[] value1 = (char[]) ReflectUtil.get(s1, "value");
char[] value2 = (char[]) ReflectUtil.get(s2, "value");
if (value1 != value2) throw new Exception("substring does NOT share the same underlying char[] with its parent String");
if (value2.length != s1.length()) throw new Exception("value2.length = " + value2.length + " != s1.length() = " + s1.length());
// second prove that the String(String) constructor trims garbage chars:
String s3 = new String(s2);
char[] value3 = (char[]) ReflectUtil.get(s3, "value");
if (value3 == value2) throw new Exception("new String shares the same underlying char[] with its String arg");
if (!(value3.length < value2.length)) throw new Exception("value3.length = " + value3.length + " is not < value2.length = " + value2.length);
return true;
}
catch (Exception e) {
LogUtil.getLogger2().logp(Level.WARNING, "StringUtil", "<clinit>", "String does not behave as expected; see cause", e);
return false;
}
}
我并不介意这个异常,因为基准测试库确实会给出结果。但是,试图将此代码编译成jar文件并作为jar运行时,会出现问题。由于异常,终端中的其余代码将无法执行。
有人有解决此问题的任何想法吗?