in bijection-core/src/main/java/com/twitter/bijection/codec/Base64.java [271:296]
public Base64(final int lineLength, final byte[] lineSeparator, final boolean urlSafe) {
super(BYTES_PER_UNENCODED_BLOCK, BYTES_PER_ENCODED_BLOCK,
lineLength,
lineSeparator == null ? 0 : lineSeparator.length);
// TODO could be simplified if there is no requirement to reject invalid line sep when length <=0
// @see test case Base64Test.testConstructors()
if (lineSeparator != null) {
if (containsAlphabetOrPad(lineSeparator)) {
final String sep = newUtf8(lineSeparator);
throw new IllegalArgumentException("lineSeparator must not contain base64 characters: [" + sep + "]");
}
if (lineLength > 0){ // null line-sep forces no chunking rather than throwing IAE
this.encodeSize = BYTES_PER_ENCODED_BLOCK + lineSeparator.length;
this.lineSeparator = new byte[lineSeparator.length];
System.arraycopy(lineSeparator, 0, this.lineSeparator, 0, lineSeparator.length);
} else {
this.encodeSize = BYTES_PER_ENCODED_BLOCK;
this.lineSeparator = null;
}
} else {
this.encodeSize = BYTES_PER_ENCODED_BLOCK;
this.lineSeparator = null;
}
this.decodeSize = this.encodeSize - 1;
this.encodeTable = urlSafe ? URL_SAFE_ENCODE_TABLE : STANDARD_ENCODE_TABLE;
}