@Test
public void testProofOfWork() throws Exception {
// This params accepts any difficulty target.
NetworkParameters params = UnitTestParams.get();
Block block = params.getDefaultSerializer().makeBlock(blockBytes);
block.setNonce(12346);
try {
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
fail();
} catch (VerificationException e) {
// Expected.
}
// Blocks contain their own difficulty target. The BlockChain verification mechanism is what
// stops real blocks
// from containing artificially weak difficulties.
block.setDifficultyTarget(Block.EASIEST_DIFFICULTY_TARGET);
// Now it should pass.
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
// Break the nonce again at the lower difficulty level so we can try solving for it.
block.setNonce(1);
try {
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
fail();
} catch (VerificationException e) {
// Expected to fail as the nonce is no longer correct.
}
// Should find an acceptable nonce.
block.solve();
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
assertEquals(block.getNonce(), 2);
}
