### Question:
StandardConversions { public static Object convertTextToText(Object source, MediaType sourceType, MediaType destinationType) { if (source == null) return null; if (sourceType == null) throw new NullPointerException("MediaType cannot be null!"); if (!sourceType.match(MediaType.TEXT_PLAIN)) throw CONTAINER.invalidMediaType(TEXT_PLAIN_TYPE, sourceType.toString()); boolean asString = destinationType.hasStringType(); Charset sourceCharset = sourceType.getCharset(); Charset destinationCharset = destinationType.getCharset(); if (sourceCharset.equals(destinationCharset)) return convertTextClass(source, destinationType, asString); byte[] byteContent = source instanceof byte[] ? (byte[]) source : source.toString().getBytes(sourceCharset); return convertTextClass(convertCharset(byteContent, sourceCharset, destinationCharset), destinationType, asString); }  static Object convertTextToText(Object source, MediaType sourceType, MediaType destinationType); static byte[] convertTextToOctetStream(Object source, MediaType sourceType); static String convertTextToObject(Object source, MediaType sourceType); static String convertTextToUrlEncoded(Object source, MediaType sourceType); static byte[] convertOctetStreamToText(byte[] source, MediaType destination); static Object convertOctetStreamToJava(byte[] source, MediaType destination, Marshaller marshaller); static byte[] convertJavaToOctetStream(Object source, MediaType sourceMediaType, Marshaller marshaller); static byte[] convertJavaToProtoStream(Object source, MediaType sourceMediaType, ImmutableSerializationContext ctx); static byte[] convertJavaToText(Object source, MediaType sourceMediaType, MediaType destinationMediaType); static Object decodeObjectContent(Object content, MediaType contentMediaType); static byte[] convertCharset(Object content, Charset fromCharset, Charset toCharset); static byte[] decodeOctetStream(Object input, MediaType octetStream); static String bytesToHex(byte[] bytes); static byte[] hexToBytes(String hex); static Object convertUrlEncodedToObject(Object content); static Object convertUrlEncodedToText(Object content, MediaType destinationType); static Object convertUrlEncodedToOctetStream(Object content); static String urlEncode(Object content, MediaType mediaType); static Object urlDecode(Object content); static Object convertOctetStreamToUrlEncoded(Object content, MediaType contentType);  }### Answer:
@Test public void textToTextConversion() { String source = "All those moments will be lost in time, like tears in rain."; byte[] sourceAs8859 = source.getBytes(ISO_8859_1); byte[] sourceAsASCII = source.getBytes(US_ASCII); Object result = StandardConversions.convertTextToText(sourceAs8859, TEXT_PLAIN.withCharset(ISO_8859_1), TEXT_PLAIN.withCharset(US_ASCII)); assertArrayEquals(sourceAsASCII, (byte[]) result); }