Use null safe method to convert bytes to hexString

This commit replaces use of
`org.spongycastle.util.encoders.Hex.toHexString()` (Not null safe) with
`org.ethereum.util.ByteUtil.toHexString()` (null safe) while logging
and in all toString() methods.

This covers only logging in the implementation(`/src/main`) and doesn't
cover any logging in tests(`/src/tests`)

Issue #1032

ethereumj-core/src/main/java/org/ethereum/config/SystemProperties.java

@@ -53,6 +53,7 @@
 import java.util.*;
 
 import static org.ethereum.crypto.HashUtil.sha3;
+import static org.ethereum.util.ByteUtil.toHexString;
 
 /**
  * Utility class to retrieve property values from the ethereumj.conf files
@@ -810,7 +811,7 @@ public boolean isFastSyncEnabled() {
     public byte[] getFastSyncPivotBlockHash() {
         if (!config.hasPath("sync.fast.pivotBlockHash")) return null;
         byte[] ret = Hex.decode(config.getString("sync.fast.pivotBlockHash"));
-        if (ret.length != 32) throw new RuntimeException("Invalid block hash length: " + Hex.toHexString(ret));
+        if (ret.length != 32) throw new RuntimeException("Invalid block hash length: " + toHexString(ret));
         return ret;
     }
 

ethereumj-core/src/main/java/org/ethereum/core/AccountState.java

@@ -25,12 +25,11 @@
 import org.ethereum.util.RLP;
 import org.ethereum.util.RLPList;
 
-import org.spongycastle.util.encoders.Hex;
-
 import java.math.BigInteger;
 
 import static org.ethereum.crypto.HashUtil.*;
 import static org.ethereum.util.FastByteComparisons.equal;
+import static org.ethereum.util.ByteUtil.toHexString;
 
 public class AccountState {
 
@@ -151,8 +150,8 @@ public boolean isEmpty() {
     public String toString() {
         String ret = "  Nonce: " + this.getNonce().toString() + "\n" +
                 "  Balance: " + getBalance() + "\n" +
-                "  State Root: " + Hex.toHexString(this.getStateRoot()) + "\n" +
-                "  Code Hash: " + Hex.toHexString(this.getCodeHash());
+                "  State Root: " + toHexString(this.getStateRoot()) + "\n" +
+                "  Code Hash: " + toHexString(this.getCodeHash());
         return ret;
     }
 }

ethereumj-core/src/main/java/org/ethereum/core/Block.java

@@ -34,6 +34,7 @@
 
 import static org.ethereum.crypto.HashUtil.sha3;
 import static org.ethereum.datasource.MemSizeEstimator.ByteArrayEstimator;
+import static org.ethereum.util.ByteUtil.toHexString;
 
 /**
  * The block in Ethereum is the collection of relevant pieces of information
@@ -69,7 +70,7 @@ private Block() {
     }
 
     public Block(byte[] rawData) {
-        logger.debug("new from [" + Hex.toHexString(rawData) + "]");
+        logger.debug("new from [" + toHexString(rawData) + "]");
         this.rlpEncoded = rawData;
     }
 
@@ -304,7 +305,7 @@ public String toString() {
         parseRLP();
 
         toStringBuff.setLength(0);
-        toStringBuff.append(Hex.toHexString(this.getEncoded())).append("\n");
+        toStringBuff.append(toHexString(this.getEncoded())).append("\n");
         toStringBuff.append("BlockData [ ");
         toStringBuff.append(header.toString());
 

ethereumj-core/src/main/java/org/ethereum/core/BlockHeaderWrapper.java

@@ -24,6 +24,7 @@
 
 import java.util.Arrays;
 import java.util.List;
+import static org.ethereum.util.ByteUtil.toHexString;
 
 /**
  * <p>Wraps {@link BlockHeader}</p>
@@ -90,7 +91,7 @@ public boolean sentBy(byte[] nodeId) {
     public String toString() {
         return "BlockHeaderWrapper {" +
                 "header=" + header +
-                ", nodeId=" + Hex.toHexString(nodeId) +
+                ", nodeId=" + toHexString(nodeId) +
                 '}';
     }
 }

ethereumj-core/src/main/java/org/ethereum/core/BlockIdentifier.java

@@ -17,15 +17,15 @@
  */
 package org.ethereum.core;
 
-import org.ethereum.util.ByteUtil;
 import org.ethereum.util.RLP;
 import org.ethereum.util.RLPList;
-import org.spongycastle.util.encoders.Hex;
 
 import java.math.BigInteger;
 import java.util.Arrays;
 
 import static org.ethereum.util.ByteUtil.byteArrayToLong;
+import static org.ethereum.util.ByteUtil.toHexString;
+
 
 /**
  * Block identifier holds block hash and number <br>
@@ -75,7 +75,7 @@ public byte[] getEncoded() {
     @Override
     public String toString() {
         return "BlockIdentifier {" +
-                "hash=" + Hex.toHexString(hash) +
+                "hash=" + toHexString(hash) +
                 ", number=" + number +
                 '}';
     }

ethereumj-core/src/main/java/org/ethereum/core/BlockchainImpl.java

@@ -67,6 +67,7 @@
 import static org.ethereum.core.Denomination.SZABO;
 import static org.ethereum.core.ImportResult.*;
 import static org.ethereum.crypto.HashUtil.sha3;
+import static org.ethereum.util.ByteUtil.toHexString;
 
 /**
  * The Ethereum blockchain is in many ways similar to the Bitcoin blockchain,
@@ -268,7 +269,7 @@ public TransactionInfo getTransactionInfo(byte[] hash) {
             }
         }
         if (txInfo == null) {
-            logger.warn("Can't find block from main chain for transaction " + Hex.toHexString(hash));
+            logger.warn("Can't find block from main chain for transaction " + toHexString(hash));
             return null;
         }
 
@@ -410,15 +411,15 @@ public synchronized ImportResult tryToConnect(final Block block) {
 
         if (logger.isDebugEnabled())
             logger.debug("Try connect block hash: {}, number: {}",
-                    Hex.toHexString(block.getHash()).substring(0, 6),
+                    toHexString(block.getHash()).substring(0, 6),
                     block.getNumber());
 
         if (blockStore.getMaxNumber() >= block.getNumber() &&
                 blockStore.isBlockExist(block.getHash())) {
 
             if (logger.isDebugEnabled())
                 logger.debug("Block already exist hash: {}, number: {}",
-                        Hex.toHexString(block.getHash()).substring(0, 6),
+                        toHexString(block.getHash()).substring(0, 6),
                         block.getNumber());
 
             // retry of well known block
@@ -582,22 +583,22 @@ public synchronized BlockSummary addImpl(Repository repo, final Block block) {
         // Sanity checks
 
         if (!FastByteComparisons.equal(block.getReceiptsRoot(), calcReceiptsTrie(receipts))) {
-            logger.warn("Block's given Receipt Hash doesn't match: {} != {}", Hex.toHexString(block.getReceiptsRoot()), Hex.toHexString(calcReceiptsTrie(receipts)));
+            logger.warn("Block's given Receipt Hash doesn't match: {} != {}", toHexString(block.getReceiptsRoot()), toHexString(calcReceiptsTrie(receipts)));
             logger.warn("Calculated receipts: " + receipts);
             repo.rollback();
             summary = null;
         }
 
         if (!FastByteComparisons.equal(block.getLogBloom(), calcLogBloom(receipts))) {
-            logger.warn("Block's given logBloom Hash doesn't match: {} != {}", Hex.toHexString(block.getLogBloom()), Hex.toHexString(calcLogBloom(receipts)));
+            logger.warn("Block's given logBloom Hash doesn't match: {} != {}", toHexString(block.getLogBloom()), toHexString(calcLogBloom(receipts)));
             repo.rollback();
             summary = null;
         }
 
         if (!FastByteComparisons.equal(block.getStateRoot(), repo.getRoot())) {
 
-            stateLogger.warn("BLOCK: State conflict or received invalid block. block: {} worldstate {} mismatch", block.getNumber(), Hex.toHexString(repo.getRoot()));
-            stateLogger.warn("Conflict block dump: {}", Hex.toHexString(block.getEncoded()));
+            stateLogger.warn("BLOCK: State conflict or received invalid block. block: {} worldstate {} mismatch", block.getNumber(), toHexString(repo.getRoot()));
+            stateLogger.warn("Conflict block dump: {}", toHexString(block.getEncoded()));
 
 //            track.rollback();
 //            repository.rollback();
@@ -612,7 +613,7 @@ public synchronized BlockSummary addImpl(Repository repo, final Block block) {
 
             if (config.exitOnBlockConflict() && !byTest) {
                 adminInfo.lostConsensus();
-                System.out.println("CONFLICT: BLOCK #" + block.getNumber() + ", dump: " + Hex.toHexString(block.getEncoded()));
+                System.out.println("CONFLICT: BLOCK #" + block.getNumber() + ", dump: " + toHexString(block.getEncoded()));
                 System.exit(1);
             } else {
                 summary = null;
@@ -718,8 +719,8 @@ private boolean isValid(Repository repo, Block block) {
             isValid = isValid(block.getHeader());
 
             // Sanity checks
-            String trieHash = Hex.toHexString(block.getTxTrieRoot());
-            String trieListHash = Hex.toHexString(calcTxTrie(block.getTransactionsList()));
+            String trieHash = toHexString(block.getTxTrieRoot());
+            String trieListHash = toHexString(calcTxTrie(block.getTransactionsList()));
 
 
             if (!trieHash.equals(trieListHash)) {
@@ -760,8 +761,8 @@ private boolean isValid(Repository repo, Block block) {
     }
 
     public boolean validateUncles(Block block) {
-        String unclesHash = Hex.toHexString(block.getHeader().getUnclesHash());
-        String unclesListHash = Hex.toHexString(HashUtil.sha3(block.getHeader().getUnclesEncoded(block.getUncleList())));
+        String unclesHash = toHexString(block.getHeader().getUnclesHash());
+        String unclesListHash = toHexString(HashUtil.sha3(block.getHeader().getUnclesEncoded(block.getUncleList())));
 
         if (!unclesHash.equals(unclesListHash)) {
             logger.warn("Block's given Uncle Hash doesn't match: {} != {}", unclesHash, unclesListHash);
@@ -792,18 +793,18 @@ public boolean validateUncles(Block block) {
 
             ByteArrayWrapper uncleHash = new ByteArrayWrapper(uncle.getHash());
             if (ancestors.contains(uncleHash)) {
-                logger.warn("Uncle is direct ancestor: " + Hex.toHexString(uncle.getHash()));
+                logger.warn("Uncle is direct ancestor: " + toHexString(uncle.getHash()));
                 return false;
             }
 
             if (usedUncles.contains(uncleHash)) {
-                logger.warn("Uncle is not unique: " + Hex.toHexString(uncle.getHash()));
+                logger.warn("Uncle is not unique: " + toHexString(uncle.getHash()));
                 return false;
             }
 
             Block uncleParent = blockStore.getBlockByHash(uncle.getParentHash());
             if (!ancestors.contains(new ByteArrayWrapper(uncleParent.getHash()))) {
-                logger.warn("Uncle has no common parent: " + Hex.toHexString(uncle.getHash()));
+                logger.warn("Uncle has no common parent: " + toHexString(uncle.getHash()));
                 return false;
             }
         }
@@ -890,12 +891,12 @@ private BlockSummary applyBlock(Repository track, Block block) {
             }
 
             stateLogger.info("block: [{}] executed tx: [{}] \n  state: [{}]", block.getNumber(), i,
-                    Hex.toHexString(track.getRoot()));
+                    toHexString(track.getRoot()));
 
             stateLogger.info("[{}] ", receipt.toString());
 
             if (stateLogger.isInfoEnabled())
-                stateLogger.info("tx[{}].receipt: [{}] ", i, Hex.toHexString(receipt.getEncoded()));
+                stateLogger.info("tx[{}].receipt: [{}] ", i, toHexString(receipt.getEncoded()));
 
             // TODO
 //            if (block.getNumber() >= config.traceStartBlock())
@@ -911,7 +912,7 @@ private BlockSummary applyBlock(Repository track, Block block) {
 
         stateLogger.info("applied reward for block: [{}]  \n  state: [{}]",
                 block.getNumber(),
-                Hex.toHexString(track.getRoot()));
+                toHexString(track.getRoot()));
 
 
         // TODO

ethereumj-core/src/main/java/org/ethereum/core/Bloom.java

@@ -18,10 +18,11 @@
 package org.ethereum.core;
 
 import org.ethereum.util.ByteUtil;
-import org.spongycastle.util.encoders.Hex;
 
 import java.util.Arrays;
 
+import static org.ethereum.util.ByteUtil.toHexString;
+
 /**
  * See http://www.herongyang.com/Java/Bit-String-Set-Bit-to-Byte-Array.html.
  *
@@ -85,7 +86,7 @@ public Bloom copy() {
 
     @Override
     public String toString() {
-        return Hex.toHexString(data);
+        return toHexString(data);
     }
 
     @Override

ethereumj-core/src/main/java/org/ethereum/core/PendingStateImpl.java

@@ -43,10 +43,11 @@
 import org.ethereum.vm.program.invoke.ProgramInvokeFactory;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.spongycastle.util.encoders.Hex;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 
+import static org.ethereum.util.ByteUtil.toHexString;
+
 /**
  * Keeps logic providing pending state management
  *
@@ -199,7 +200,7 @@ private void fireTxUpdate(TransactionReceipt txReceipt, PendingTransactionState
         if (logger.isDebugEnabled()) {
             logger.debug(String.format("PendingTransactionUpdate: (Tot: %3s) %12s : %s %8s %s [%s]",
                     getPendingTransactions().size(),
-                    state, Hex.toHexString(txReceipt.getTransaction().getSender()).substring(0, 8),
+                    state, toHexString(txReceipt.getTransaction().getSender()).substring(0, 8),
                     ByteUtil.byteArrayToLong(txReceipt.getTransaction().getNonce()),
                     block.getShortDescr(), txReceipt.getError()));
         }
@@ -351,7 +352,7 @@ private void clearOutdated(final long blockNumber) {
                 logger.trace(
                         "Clear outdated pending transaction, block.number: [{}] hash: [{}]",
                         tx.getBlockNumber(),
-                        Hex.toHexString(tx.getHash())
+                        toHexString(tx.getHash())
                 );
 
         pendingTransactions.removeAll(outdated);
@@ -364,7 +365,7 @@ private void clearPending(Block block, List<TransactionReceipt> receipts) {
 
             if (pendingTransactions.remove(pend)) {
                 try {
-                    logger.trace("Clear pending transaction, hash: [{}]", Hex.toHexString(tx.getHash()));
+                    logger.trace("Clear pending transaction, hash: [{}]", toHexString(tx.getHash()));
                     TransactionReceipt receipt;
                     if (receipts != null) {
                         receipt = receipts.get(i);
@@ -404,7 +405,7 @@ private void updateState(Block block) {
 
     private TransactionReceipt executeTx(Transaction tx) {
 
-        logger.trace("Apply pending state tx: {}", Hex.toHexString(tx.getHash()));
+        logger.trace("Apply pending state tx: {}", toHexString(tx.getHash()));
 
         Block best = getBestBlock();
 

ethereumj-core/src/main/java/org/ethereum/core/TransactionExecutor.java

@@ -33,7 +33,6 @@
 import org.ethereum.vm.program.invoke.ProgramInvokeFactory;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.spongycastle.util.encoders.Hex;
 
 import java.math.BigInteger;
 import java.util.List;
@@ -45,6 +44,7 @@
 import static org.ethereum.util.ByteUtil.toHexString;
 import static org.ethereum.vm.VMUtils.saveProgramTraceFile;
 import static org.ethereum.vm.VMUtils.zipAndEncode;
+import static org.ethereum.util.ByteUtil.toHexString;
 
 /**
  * @author Roman Mandeleil
@@ -218,7 +218,7 @@ private void call() {
             if (!localCall && m_endGas.compareTo(spendingGas) < 0) {
                 // no refund
                 // no endowment
-                execError("Out of Gas calling precompiled contract 0x" + Hex.toHexString(targetAddress) +
+                execError("Out of Gas calling precompiled contract 0x" + toHexString(targetAddress) +
                         ", required: " + spendingGas + ", left: " + m_endGas);
                 m_endGas = BigInteger.ZERO;
                 return;
@@ -230,7 +230,7 @@ private void call() {
                 Pair<Boolean, byte[]> out = precompiledContract.execute(tx.getData());
 
                 if (!out.getLeft()) {
-                    execError("Error executing precompiled contract 0x" + Hex.toHexString(targetAddress));
+                    execError("Error executing precompiled contract 0x" + toHexString(targetAddress));
                     m_endGas = BigInteger.ZERO;
                     return;
                 }
@@ -262,7 +262,7 @@ private void create() {
 
         AccountState existingAddr = cacheTrack.getAccountState(newContractAddress);
         if (existingAddr != null && existingAddr.isContractExist(blockchainConfig)) {
-            execError("Trying to create a contract with existing contract address: 0x" + Hex.toHexString(newContractAddress));
+            execError("Trying to create a contract with existing contract address: 0x" + toHexString(newContractAddress));
             m_endGas = BigInteger.ZERO;
             return;
         }
@@ -426,12 +426,12 @@ public TransactionExecutionSummary finalization() {
 
         // Refund for gas leftover
         track.addBalance(tx.getSender(), summary.getLeftover().add(summary.getRefund()));
-        logger.info("Pay total refund to sender: [{}], refund val: [{}]", Hex.toHexString(tx.getSender()), summary.getRefund());
+        logger.info("Pay total refund to sender: [{}], refund val: [{}]", toHexString(tx.getSender()), summary.getRefund());
 
         // Transfer fees to miner
         track.addBalance(coinbase, summary.getFee());
         touchedAccounts.add(coinbase);
-        logger.info("Pay fees to miner: [{}], feesEarned: [{}]", Hex.toHexString(coinbase), summary.getFee());
+        logger.info("Pay fees to miner: [{}], feesEarned: [{}]", toHexString(coinbase), summary.getFee());
 
         if (result != null) {
             logs = result.getLogInfoList();