### Question:
StringCaseUtils { public static boolean isUpperCamelCase(String string) { if (StringUtils.isBlank(string)) { return false; } return UPPER_CAMEL_CASE.matcher(string).matches(); } private  StringCaseUtils(); static boolean isLowerCamelCase(String string); static boolean isUpperCamelCase(String string); static boolean isUpperHyphenCase(String string); static boolean isMatchCase(String expectedCase, String string);  }### Answer:
@Test public void isUpperCamelCase() { assertThat(StringCaseUtils.isUpperCamelCase("")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("A")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("A0")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("Aa")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("AA")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("0")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("00")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("0a")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("0A")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("a")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("a0")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("aa")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("aA")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("A00")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("A0a")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("A0A")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("Aa0")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("Aaa")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("AaA")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("AaA0")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("AaAa")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("AaAA")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("AaA00")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("AaA0a")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("AaA0A")).isTrue(); assertThat(StringCaseUtils.isUpperCamelCase("_aaA00")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("a_aA00")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("aa_A00")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("aaA_00")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("aaA0_0")).isFalse(); assertThat(StringCaseUtils.isUpperCamelCase("aaA00_")).isFalse(); }