JSON.json(Locale) throw StackOverflowError, into the dead loop

[takeseem]

public class JSONTest {
	
	@Test
	public void testLocale() throws Exception {
		Locale locale = Locale.US;
		String result = JSON.json(locale);
		//check JSON.json(Locale) into the dead loop
		/**
		java.lang.StackOverflowError
			at java.lang.StringBuilder.append(StringBuilder.java:136)
			at sun.util.locale.provider.LocaleResources.getLocaleName(LocaleResources.java:230)
			at java.util.Locale.getDisplayName(Locale.java:1879)
			at java.util.Locale.getDisplayName(Locale.java:1845)
			at com.alibaba.dubbo.common.bytecode.Wrapper1.getPropertyValue(Wrapper1.java)
			at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:126)
			at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:73)
			at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:130)
			at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:73)
			at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:130)
			at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:73)
			at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:130)
		 */
		Assert.assertEquals(result, locale.toString());
	}

[takeseem]

fix from dubbo:master, 2.5.7 : GenericJSONConverter主要是用在日志部分输出，所以当我们输出locale对象时就发生stack溢出。

java.lang.StackOverflowError
	at com.alibaba.dubbo.common.json.JSONWriter.valueString(JSONWriter.java:189)
	at com.alibaba.dubbo.common.json.GenericJSONConverter$7.encode(GenericJSONConverter.java:100)
	at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:338)
	at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:347)
	at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:395)
	at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:347)
	at com.alibaba.dubbo.common.json.GenericJSONConverter.writeValue(GenericJSONConverter.java:395)

[takeseem]

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