1. Added Transfer class for simplifying Ether transactions in line with working with smart contracts.

2. Added generated Greeter.
3. Creation of isIntegerValue utility function.
4. Added Gradle shadow plugin for building fat jars.
5. Created command line tools for managing wallets.
6. Bumped version.

Author: conor10

README.rst

@@ -68,15 +68,15 @@ Maven
    <dependency>
      <groupId>org.web3j</groupId>
      <artifactId>core</artifactId>
-     <version>1.0.1</version>
+     <version>1.0.2</version>
    </dependency>
 
 Gradle
 ------
 
 .. code-block:: groovy
 
-   compile ('org.web3j:core:1.0.1')
+   compile ('org.web3j:core:1.0.2')
 
 
 Start a client

build.gradle

@@ -3,7 +3,8 @@ buildscript {
         mavenCentral()
     }
     dependencies {
-        classpath "io.codearte.gradle.nexus:gradle-nexus-staging-plugin:0.5.3"
+        classpath 'io.codearte.gradle.nexus:gradle-nexus-staging-plugin:0.5.3'
+        classpath 'com.github.jengelman.gradle.plugins:shadow:1.2.4'
     }
 }
 
@@ -21,9 +22,10 @@ apply plugin: 'maven'
 apply plugin: 'signing'
 apply plugin: 'idea'
 apply plugin: 'io.codearte.nexus-staging'
+apply plugin: 'com.github.johnrengelman.shadow'
 
 group 'org.web3j'
-version '1.0.1'
+version '1.0.2'
 
 sourceCompatibility = 1.8
 
@@ -59,6 +61,7 @@ ext {
 
 repositories {
     mavenCentral()
+    jcenter()
 }
 
 // See https://www.petrikainulainen.net/programming/gradle/getting-started-with-gradle-integration-testing/

docs/source/getting_started.rst

@@ -11,15 +11,15 @@ Maven
    <dependency>
      <groupId>org.web3j</groupId>
      <artifactId>core</artifactId>
-     <version>1.0.1</version>
+     <version>1.0.2</version>
    </dependency>
 
 Gradle
 ------
 
 .. code-block:: groovy
 
-   compile ('org.web3j:core:1.0.1')
+   compile ('org.web3j:core:1.0.2')
 
 
 Start a client

src/integration-test/java/org/web3j/generated/Greeter.java

@@ -0,0 +1,49 @@
+package org.web3j.generated;
+
+import java.lang.String;
+import java.math.BigInteger;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.concurrent.Future;
+import org.web3j.abi.Contract;
+import org.web3j.abi.FunctionEncoder;
+import org.web3j.abi.TypeReference;
+import org.web3j.abi.datatypes.Function;
+import org.web3j.abi.datatypes.Utf8String;
+import org.web3j.crypto.Credentials;
+import org.web3j.protocol.Web3j;
+import org.web3j.protocol.core.methods.response.TransactionReceipt;
+
+/**
+ * <p>Auto generated code.<br>
+ * <strong>Do not modifiy!</strong><br>
+ * Please use {@link org.web3j.codegen.SolidityFunctionWrapperGenerator} to update.</p>
+ */
+public final class Greeter extends Contract {
+    private static final String BINARY = "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";
+
+    private Greeter(String contractAddress, Web3j web3j, Credentials credentials) {
+        super(contractAddress, web3j, credentials);
+    }
+
+    public Future<TransactionReceipt> kill() {
+        Function function = new Function<>("kill", Arrays.asList(), Collections.emptyList());
+        return executeTransactionAsync(function);
+    }
+
+    public Future<Utf8String> greet() {
+        Function function = new Function<>("greet", 
+                Arrays.asList(), 
+                Arrays.asList(new TypeReference<Utf8String>() {}));
+        return executeCallSingleValueReturnAsync(function);
+    }
+
+    public static Future<Greeter> deploy(Web3j web3j, Credentials credentials, BigInteger initialValue, Utf8String _greeting) {
+        String encodedConstructor = FunctionEncoder.encodeConstructor(Arrays.asList(_greeting));
+        return deployAsync(Greeter.class, web3j, credentials, BINARY, encodedConstructor, initialValue);
+    }
+
+    public static Greeter load(String contractAddress, Web3j web3j, Credentials credentials) {
+        return new Greeter(contractAddress, web3j, credentials);
+    }
+}

src/integration-test/java/org/web3j/protocol/scenarios/SendEtherIT.java

@@ -1,9 +1,11 @@
 package org.web3j.protocol.scenarios;
 
+import java.math.BigDecimal;
 import java.math.BigInteger;
 
 import org.junit.Test;
 
+import org.web3j.abi.Transfer;
 import org.web3j.protocol.core.methods.request.Transaction;
 import org.web3j.protocol.core.methods.response.EthSendTransaction;
 import org.web3j.protocol.core.methods.response.TransactionReceipt;
@@ -17,6 +19,7 @@
  * Simple integration test to demonstrate sending of Ether between parties.
  */
 public class SendEtherIT extends Scenario {
+
     @Test
     public void testTransferEther() throws Exception {
         unlockAccount();
@@ -38,4 +41,31 @@ public void testTransferEther() throws Exception {
 
         assertThat(transactionReceipt.getTransactionHash(), is(transactionHash));
     }
+
+    /*
+    Valid transaction reciept:
+    "{"jsonrpc":"2.0",
+        "id":1,
+        "result":{
+           "blockHash":"0x35a865cf2ba4efc3642b17a651f9e896dfebcdea39bfd0741b6f629e1be31a27",
+           "blockNumber":"0x1c155f",
+           "contractAddress":null,
+           "cumulativeGasUsed":"0x5208",
+           "from":"0x19e03255f667bdfd50a32722df860b1eeaf4d635",
+           "gasUsed":"0x5208",
+           "logs":[
+
+           ],
+           "root":"327e1e81c85cb710fe81cb8c0f824e9e49c3bf200e5e1149f589140145df10e3",
+           "to":"0x9c98e381edc5fe1ac514935f3cc3edaa764cf004",
+           "transactionHash":"0x16e41aa9d97d1c3374a4cb9599febdb24d4d5648b607c99e01a8e79e3eab2c34",
+           "transactionIndex":"0x0"
+        }
+     */
+    @Test
+    public void testTransfer() throws Exception {
+        TransactionReceipt transactionReceipt = Transfer.sendFunds(
+                parity, ALICE, BOB.getAddress(), BigDecimal.valueOf(0.2), Convert.Unit.ETHER);
+        assertFalse(transactionReceipt.getBlockHash().isEmpty());
+    }
 }

src/main/java/org/web3j/abi/Contract.java

@@ -13,35 +13,27 @@
 import org.web3j.abi.datatypes.Function;
 import org.web3j.abi.datatypes.Type;
 import org.web3j.crypto.Credentials;
-import org.web3j.crypto.TransactionEncoder;
 import org.web3j.protocol.Web3j;
 import org.web3j.protocol.core.DefaultBlockParameterName;
 import org.web3j.protocol.core.methods.request.RawTransaction;
 import org.web3j.protocol.core.methods.request.Transaction;
 import org.web3j.protocol.core.methods.response.*;
 import org.web3j.protocol.exceptions.TransactionTimeoutException;
-import org.web3j.utils.Numeric;
 
 
 /**
  * Solidity contract type abstraction for interacting with smart contracts via native Java types.
  */
-public abstract class Contract {
+public abstract class Contract extends ManagedTransaction {
 
     private static final BigInteger GAS_PRICE = BigInteger.valueOf(50_000_000_000L);
     private static final BigInteger GAS_LIMIT = BigInteger.valueOf(2_000_000);
 
-    private static final int SLEEP_DURATION = 15000;
-    private static final int ATTEMPTS = 40;
-
     private String contractAddress;
-    private Web3j web3j;
-    private Credentials credentials;
 
     protected Contract(String contractAddress, Web3j web3j, Credentials credentials) {
+        super(web3j, credentials);
         this.contractAddress = contractAddress;
-        this.web3j = web3j;
-        this.credentials = credentials;
     }
 
     public String getContractAddress() {
@@ -138,21 +130,6 @@ protected TransactionReceipt executeTransaction(
         return signAndSend(rawTransaction);
     }
 
-    private TransactionReceipt signAndSend(RawTransaction rawTransaction)
-            throws InterruptedException, ExecutionException, TransactionTimeoutException{
-        byte[] signedMessage = TransactionEncoder.signMessage(rawTransaction, credentials);
-        String hexValue = Numeric.toHexString(signedMessage);
-
-        // This might be a good candidate for using functional composition with CompletableFutures
-        EthSendTransaction transactionResponse = web3j.ethSendRawTransaction(hexValue)
-                .sendAsync().get();
-
-        String transactionHash = transactionResponse.getTransactionHash();
-
-        return waitForTransactionReceipt(transactionHash);
-    }
-
-
     /**
      * Execute the provided function as a transaction asynchronously.
      *
@@ -173,47 +150,6 @@ protected Future<TransactionReceipt> executeTransactionAsync(Function function)
         return result;
     }
 
-    private BigInteger getNonce(String address) throws InterruptedException, ExecutionException {
-        EthGetTransactionCount ethGetTransactionCount = web3j.ethGetTransactionCount(
-                address, DefaultBlockParameterName.LATEST).sendAsync().get();
-
-        return ethGetTransactionCount.getTransactionCount();
-    }
-
-    private TransactionReceipt waitForTransactionReceipt(
-            String transactionHash) throws InterruptedException, ExecutionException,
-            TransactionTimeoutException {
-
-        return getTransactionReceipt(transactionHash, SLEEP_DURATION, ATTEMPTS);
-    }
-
-    private TransactionReceipt getTransactionReceipt(
-            String transactionHash, int sleepDuration, int attempts)
-            throws InterruptedException, ExecutionException, TransactionTimeoutException {
-
-        Optional<TransactionReceipt> receiptOptional =
-                sendTransactionReceiptRequest(transactionHash);
-        for (int i = 0; i < attempts; i++) {
-            if (!receiptOptional.isPresent()) {
-                Thread.sleep(sleepDuration);
-                receiptOptional = sendTransactionReceiptRequest(transactionHash);
-            } else {
-                return receiptOptional.get();
-            }
-        }
-
-        throw new TransactionTimeoutException("Transaction receipt was not generated after " +
-                ((sleepDuration * attempts) / 1000 + " seconds"));
-    }
-
-    private Optional<TransactionReceipt> sendTransactionReceiptRequest(
-            String transactionHash) throws InterruptedException, ExecutionException {
-        EthGetTransactionReceipt transactionReceipt =
-                web3j.ethGetTransactionReceipt(transactionHash).sendAsync().get();
-
-        return transactionReceipt.getTransactionReceipt();
-    }
-
     protected EventValues extractEventParameters(
             Event event, TransactionReceipt transactionReceipt) {
 

src/main/java/org/web3j/abi/ManagedTransaction.java

@@ -0,0 +1,93 @@
+package org.web3j.abi;
+
+import java.math.BigInteger;
+import java.util.Optional;
+import java.util.concurrent.ExecutionException;
+
+import org.web3j.crypto.Credentials;
+import org.web3j.crypto.TransactionEncoder;
+import org.web3j.protocol.Web3j;
+import org.web3j.protocol.core.DefaultBlockParameterName;
+import org.web3j.protocol.core.methods.request.RawTransaction;
+import org.web3j.protocol.core.methods.response.EthGetTransactionCount;
+import org.web3j.protocol.core.methods.response.EthGetTransactionReceipt;
+import org.web3j.protocol.core.methods.response.EthSendTransaction;
+import org.web3j.protocol.core.methods.response.TransactionReceipt;
+import org.web3j.protocol.exceptions.TransactionTimeoutException;
+import org.web3j.utils.Numeric;
+
+
+/**
+ * Generic transaction manager
+ */
+public abstract class ManagedTransaction {
+
+    private static final BigInteger GAS_PRICE = BigInteger.valueOf(50_000_000_000L);
+    private static final BigInteger GAS_LIMIT = BigInteger.valueOf(2_000_000);
+
+    private static final int SLEEP_DURATION = 15000;
+    private static final int ATTEMPTS = 40;
+
+    protected Web3j web3j;
+    protected Credentials credentials;
+
+    protected ManagedTransaction(Web3j web3j, Credentials credentials) {
+        this.web3j = web3j;
+        this.credentials = credentials;
+    }
+
+    protected TransactionReceipt signAndSend(RawTransaction rawTransaction)
+            throws InterruptedException, ExecutionException, TransactionTimeoutException{
+        byte[] signedMessage = TransactionEncoder.signMessage(rawTransaction, credentials);
+        String hexValue = Numeric.toHexString(signedMessage);
+
+        // This might be a good candidate for using functional composition with CompletableFutures
+        EthSendTransaction transactionResponse = web3j.ethSendRawTransaction(hexValue)
+                .sendAsync().get();
+
+        String transactionHash = transactionResponse.getTransactionHash();
+
+        return waitForTransactionReceipt(transactionHash);
+    }
+
+    protected BigInteger getNonce(String address) throws InterruptedException, ExecutionException {
+        EthGetTransactionCount ethGetTransactionCount = web3j.ethGetTransactionCount(
+                address, DefaultBlockParameterName.LATEST).sendAsync().get();
+
+        return ethGetTransactionCount.getTransactionCount();
+    }
+
+    private TransactionReceipt waitForTransactionReceipt(
+            String transactionHash) throws InterruptedException, ExecutionException,
+            TransactionTimeoutException {
+
+        return getTransactionReceipt(transactionHash, SLEEP_DURATION, ATTEMPTS);
+    }
+
+    private TransactionReceipt getTransactionReceipt(
+            String transactionHash, int sleepDuration, int attempts)
+            throws InterruptedException, ExecutionException, TransactionTimeoutException {
+
+        Optional<TransactionReceipt> receiptOptional =
+                sendTransactionReceiptRequest(transactionHash);
+        for (int i = 0; i < attempts; i++) {
+            if (!receiptOptional.isPresent()) {
+                Thread.sleep(sleepDuration);
+                receiptOptional = sendTransactionReceiptRequest(transactionHash);
+            } else {
+                return receiptOptional.get();
+            }
+        }
+
+        throw new TransactionTimeoutException("Transaction receipt was not generated after " +
+                ((sleepDuration * attempts) / 1000 + " seconds"));
+    }
+
+    private Optional<TransactionReceipt> sendTransactionReceiptRequest(
+            String transactionHash) throws InterruptedException, ExecutionException {
+        EthGetTransactionReceipt transactionReceipt =
+                web3j.ethGetTransactionReceipt(transactionHash).sendAsync().get();
+
+        return transactionReceipt.getTransactionReceipt();
+    }
+}