Collapse foreach loops using Stream#collect

ethereumj-core/src/main/java/org/ethereum/db/BlockStore.java

@@ -15,6 +15,7 @@ import java.math.BigInteger;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.stream.Collectors;
 
 /**
  * @author Roman Mandeleil
@@ -73,9 +74,7 @@ public class BlockStore {
                 setParameter("limit", block.getNumber() - qty).
                 setMaxResults(qty).list();
 
-        for (byte[] h : result) {
+        hashes.addAll(result.stream().collect(Collectors.toList()));
-            hashes.add(h);
-        }
 
         return hashes;
     }

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

@@ -153,13 +153,13 @@ public class AccountState {
             checked.add(key);
         }
 
-        for (DataWord key : expectedKeys) {
+        expectedKeys.stream()
-            if (!checked.contains(key)) {
+                .filter(key -> !checked.contains(key))
+                .forEach(key -> {
                     String formatedString = String.format("Account: %s: doesn't exist expected storage key: %s",
                             Hex.toHexString(this.address), key.toString());
                     results.add(formatedString);
-            }
+                });
-        }
 
         return results;
     }

ethereumj-core/src/main/java/org/ethereum/net/eth/BlockHashesMessage.java

@@ -7,6 +7,7 @@ import org.ethereum.util.Utils;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.stream.Collectors;
 
 import static org.ethereum.net.eth.EthMessageCodes.BLOCK_HASHES;
 
@@ -45,8 +46,10 @@ public class BlockHashesMessage extends EthMessage {
     private void encode() {
         List<byte[]> encodedElements = new ArrayList<>();
         encodedElements.add(RLP.encodeByte(BLOCK_HASHES.asByte()));
-        for (byte[] blockHash : blockHashes)
+        encodedElements.addAll(
-            encodedElements.add(RLP.encodeElement(blockHash));
+                blockHashes.stream()
+                        .map(RLP::encodeElement)
+                        .collect(Collectors.toList()));
         byte[][] encodedElementArray = encodedElements
                 .toArray(new byte[encodedElements.size()][]);
         this.encoded = RLP.encodeList(encodedElementArray);

ethereumj-core/src/main/java/org/ethereum/net/eth/BlocksMessage.java

@@ -7,6 +7,7 @@ import org.ethereum.util.RLPList;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Vector;
+import java.util.stream.Collectors;
 
 import static org.ethereum.net.eth.EthMessageCodes.BLOCKS;
 
@@ -45,9 +46,10 @@ public class BlocksMessage extends EthMessage {
         List<byte[]> encodedElements = new Vector<>();
         encodedElements.add(RLP.encodeByte(BLOCKS.asByte()));
 
-        for (Block block : blocks) {
+        encodedElements.addAll(
-            encodedElements.add(block.getEncoded());
+                blocks.stream()
-        }
+                        .map(Block::getEncoded)
+                        .collect(Collectors.toList()));
 
         byte[][] encodedElementArray = encodedElements
                 .toArray(new byte[encodedElements.size()][]);

ethereumj-core/src/main/java/org/ethereum/net/eth/GetBlocksMessage.java

@@ -6,6 +6,7 @@ import org.ethereum.util.Utils;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.stream.Collectors;
 
 import static org.ethereum.net.eth.EthMessageCodes.GET_BLOCKS;
 
@@ -43,8 +44,10 @@ public class GetBlocksMessage extends EthMessage {
     private void encode() {
         List<byte[]> encodedElements = new ArrayList<>();
         encodedElements.add(RLP.encodeByte(GET_BLOCKS.asByte()));
-        for (byte[] hash : blockHashes)
+        encodedElements.addAll(
-            encodedElements.add(RLP.encodeElement(hash));
+                blockHashes.stream()
+                        .map(RLP::encodeElement)
+                        .collect(Collectors.toList()));
         byte[][] encodedElementArray = encodedElements
                 .toArray(new byte[encodedElements.size()][]);
         this.encoded = RLP.encodeList(encodedElementArray);

ethereumj-core/src/main/java/org/ethereum/net/eth/TransactionsMessage.java

@@ -8,6 +8,7 @@ import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import static org.ethereum.net.eth.EthMessageCodes.TRANSACTIONS;
 
@@ -51,8 +52,10 @@ public class TransactionsMessage extends EthMessage {
     private void encode() {
         List<byte[]> encodedElements = new ArrayList<>();
         encodedElements.add(RLP.encodeByte(TRANSACTIONS.asByte()));
-        for (Transaction tx : transactions)
+        encodedElements.addAll(
-            encodedElements.add(tx.getEncoded());
+                transactions.stream()
+                        .map(Transaction::getEncoded)
+                        .collect(Collectors.toList()));
         byte[][] encodedElementArray = encodedElements
                 .toArray(new byte[encodedElements.size()][]);
         this.encoded = RLP.encodeList(encodedElementArray);

ethereumj-core/src/main/java/org/ethereum/trie/TrieImpl.java

@@ -12,10 +12,10 @@ import org.slf4j.LoggerFactory;
 import org.spongycastle.util.encoders.Hex;
 
 import java.util.Arrays;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import static java.util.Arrays.copyOfRange;
 import static org.ethereum.crypto.HashUtil.EMPTY_TRIE_HASH;
@@ -450,13 +450,9 @@ public class TrieImpl implements Trie {
 
         Set<byte[]> hashSet = collectAction.getCollectedHashes();
         Map<ByteArrayWrapper, Node> nodes = this.getCache().getNodes();
-        Set<ByteArrayWrapper> toRemoveSet = new HashSet<>();
+        Set<ByteArrayWrapper> toRemoveSet = nodes.keySet().stream()
-
+                .filter(key -> !hashSet.contains(key.getData()))
-        for (ByteArrayWrapper key : nodes.keySet()) {
+                .collect(Collectors.toSet());
-            if (!hashSet.contains(key.getData())) {
-                toRemoveSet.add(key);
-            }
-        }
 
         for (ByteArrayWrapper key : toRemoveSet) {