修复Pair反序列化报错问题

hutool-json/src/test/java/cn/hutool/json/IssueI6SZYBTest.java

@@ -0,0 +1,30 @@
+package cn.hutool.json;
+
+import cn.hutool.core.lang.Pair;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.AbstractMap;
+import java.util.Map;
+
+public class IssueI6SZYBTest {
+	@Test
+	public void pairTest() {
+		Pair<Integer,Integer> pair = Pair.of(1, 2);
+		String jsonStr = JSONUtil.toJsonStr(pair);
+		Assert.assertEquals("{\"key\":1,\"value\":2}", jsonStr);
+
+		final Pair bean = JSONUtil.toBean(jsonStr, Pair.class);
+		Assert.assertEquals(pair, bean);
+	}
+
+	@Test
+	public void entryTest() {
+		Map.Entry<String,Integer> pair = new AbstractMap.SimpleEntry<>("1", 2);
+		String jsonStr = JSONUtil.toJsonStr(pair);
+		Assert.assertEquals("{\"1\":2}", jsonStr);
+
+		final Map.Entry bean = JSONUtil.toBean(jsonStr, AbstractMap.SimpleEntry.class);
+		Assert.assertEquals(pair, bean);
+	}
+}