StringUtils { public static String toString(byte[] bytes, String charsetName) throws UnsupportedEncodingException { return charsetName == null ? new String(bytes) : new String(bytes, charsetName); }  static boolean isEmpty(CharSequence cs); static boolean isNotEmpty(CharSequence cs); static boolean isBlank(CharSequence cs); static boolean isNotBlank(CharSequence cs); static String trim(String str); static String trimToNull(String str); static String trimToEmpty(String str); static String toString(byte[] bytes, String charsetName); static String defaultString(final Object str); static String toString(Object o, String defaultVal); static String toString(Object o); static String objectsToString(Object[] args); static boolean equals(CharSequence s1, CharSequence s2); static String[] split(String src, String separator); static String[] splitWithCommaOrSemicolon(String src); static String join(String[] strings, String separator); static String joinWithComma(String... strings); static String substringAfter(String str, String separator); static String substringBefore(String str, String separator); static final String EMPTY; static final String CONTEXT_SEP; static final String ALL; static final String DEFAULT; static final String TRUE; static final String FALSE; static final String NULL; static final String[] EMPTY_STRING_ARRAY; }
@Test public void testToString() { Assert.assertEquals(null, StringUtils.toString(null)); Assert.assertEquals("Bean:11", StringUtils.toString(new Bean("11"))); Assert.assertEquals(null, StringUtils.toString((Object) null, null)); Assert.assertEquals("1", StringUtils.toString((Object) null, "1")); Assert.assertEquals("Bean:11", StringUtils.toString(new Bean("11"), null)); Assert.assertEquals(null, StringUtils.objectsToString(null)); Assert.assertEquals("[]", StringUtils.objectsToString(new Object[0])); Assert.assertEquals("[1,22]", StringUtils.objectsToString(new Object[] { 1, "22" })); Assert.assertEquals("[1,Bean:11]", StringUtils.objectsToString(new Object[] { 1, new Bean("11") })); }