MetadataHeadersValueValidator extends AbstractHeaderValueValidator { static MetadataHeadersValueValidator getInstance() { return new MetadataHeadersValueValidator(); } private  MetadataHeadersValueValidator();   }
@Test public void validateValidMetadataHeadersCharSequence() { final MetadataHeaders metadataHeaders = MetadataHeaders.newInstance(); metadataHeaders.add(MetadataHeader.of(MetadataHeaderKey.parse("/*/issuedBy"), JsonValue.of("me"))); metadataHeaders.add(MetadataHeader.of(MetadataHeaderKey.parse("/foo/bar"), JsonValue.of("baz"))); final MetadataHeadersValueValidator underTest = MetadataHeadersValueValidator.getInstance(); assertThatCode(() -> underTest.accept(DittoHeaderDefinition.PUT_METADATA, metadataHeaders.toJsonString())) .doesNotThrowAnyException(); }