in datasketches-memory-java8/src/main/java/org/apache/datasketches/memory/internal/Util.java [132:159]
public static final String characterPad(final String s, final int fieldLength,
final char padChar, final boolean postpend) {
final char[] chArr = s.toCharArray();
final int sLen = chArr.length;
if (sLen < fieldLength) {
final char[] out = new char[fieldLength];
final int blanks = fieldLength - sLen;
if (postpend) {
for (int i = 0; i < sLen; i++) {
out[i] = chArr[i];
}
for (int i = sLen; i < fieldLength; i++) {
out[i] = padChar;
}
} else { //prepend
for (int i = 0; i < blanks; i++) {
out[i] = padChar;
}
for (int i = blanks; i < fieldLength; i++) {
out[i] = chArr[i - blanks];
}
}
return String.valueOf(out);
}
return s;
}