断言列表具有相同的对象，但hamcrest失败

Question

我有两个列表，我想验证它们具有相同顺序的相同对象。 由于这个原因，我正在使用hamcrest，但由于某些原因，我不明白我得到了一个编译错误：

有人可以解释该错误，我该如何解决？

List<String> actual = Arrays.asList("asd", "bc", "qwe");
List<String> expected = Arrays.asList("asd", "bc", "qwe");

assertThat(actual,IsIterableContainingInAnyOrder.containsInAnyOrder(expected));

这是错误消息：

com.me.Test.java:[160,1] no suitable method found for 
assertThat(java.util.List<java.lang.String>,org.hamcrest.Matcher<java.lang.Iterable<? 
extends java.util.List<java.lang.String>>>)
method org.junit.Assert.<T>assertThat(T,org.hamcrest.Matcher<T>) is not applicable
(no instance(s) of type variable(s) T exist so that argument type
org.hamcrest.Matcher<java.lang.Iterable<? extends java.util.List<java.lang.String>>> conforms to formal parameter type org.hamcrest.Matcher<T>)
method org.junit.Assert.<T>assertThat(java.lang.String,T,org.hamcrest.Matcher<T>) is not applicable
(cannot instantiate from arguments because actual and formal argument lists differ in length)

Answer 1

查看IsIterableContainingInAnyOrder.containsInAnyOrder的javadoc 。 假设您没有尝试将Matcher传递给此方法，则应将数组（或varargs）传递给此方法，例如：

assertThat(actual, IsIterableContainingInAnyOrder.containsInAnyOrder("qwe", "asd", "bc"));

要么

assertThat(actual,IsIterableContainingInAnyOrder.containsInAnyOrder(expected.toArray(new String[expected.size()])));

Answer 2

我只会使用Set，或者先对数组进行排序。

Collectons.sort(actual); 
Collections.sort(expected); // if not sorted already.
assertEquals(expected, actual);

或在Java 8中

actual.sort();
expected.sort();
assertEquals(expected, actual);

或者如果重复项可以忽略

assertEquals(new HashSet<>(expected), new HashSet<>(actual));