### Question:
BaseBinaryStorageSvcImpl implements IBinaryStorageSvc { @Override public String newBlobId() { StringBuilder b = new StringBuilder(); for (int i = 0; i < ID_LENGTH; i++) { int nextInt = Math.abs(myRandom.nextInt()); b.append(CHARS.charAt(nextInt % CHARS.length())); } return b.toString(); } BaseBinaryStorageSvcImpl(); @Override int getMaximumBinarySize(); @Override void setMaximumBinarySize(int theMaximumBinarySize); @Override int getMinimumBinarySize(); @Override void setMinimumBinarySize(int theMinimumBinarySize); @Override String newBlobId(); @Override boolean shouldStoreBlob(long theSize, IIdType theResourceId, String theContentType);  }### Answer:
@Test public void testNewRandomId() { MemoryBinaryStorageSvcImpl svc = new MemoryBinaryStorageSvcImpl(); String id = svc.newBlobId(); ourLog.info(id); assertThat(id, matchesPattern("^[a-zA-Z0-9]{100}$")); }