Modify contract usage in readme file ！

README.md

@@ -596,28 +596,31 @@ JD区块链的核心对象包括：
 
     // 合约地址
     String contractAddressBase58 = "";
-
-    // Event
-    String event = "";
-
-    // args（注意参数的格式）
-    byte[] args = "20##30##abc".getBytes();
-
-
-    // 提交合约执行代码
-    txTemp.contractEvents().send(contractAddressBase58, event, args);
-
-    // TX 准备就绪；
-    PreparedTransaction prepTx = txTemp.prepare();
-
-    // 生成私钥并使用私钥进行签名；
-    CryptoKeyPair keyPair = getSponsorKey();
-
-    prepTx.sign(keyPair);
-
-    // 提交交易；
-    TransactionResponse transactionResponse = prepTx.commit();
-
-    assertTrue(transactionResponse.isSuccess());
+    
+    // 使用接口方式调用合约
+    TransferContract transferContract = txTpl.contract(contractAddress, TransferContract.class);
+    
+    // 使用decode方式调用合约内部方法（create方法）
+    // 返回GenericValueHolder可通过get方法获取结果，但get方法需要在commit调用后执行
+    GenericValueHolder<String> result = ContractReturnValue.decode(transferContract.create(address, account, money));
+    
+    PreparedTransaction ptx = txTpl.prepare();
+    
+    ptx.sign(adminKey);
+    
+    TransactionResponse transactionResponse = ptx.commit();
+    
+    String cotractExecResult = result.get();
+    
+    // TransactionResponse也提供了可供查询结果的接口
+    OperationResult[] operationResults = transactionResponse.getOperationResults();
+    
+    // 通过OperationResult获取结果
+    for (int i = 0; i < operationResults.length; i++) {
+        OperationResult opResult = operationResults[i];
+        System.out.printf("Operation[%s].result = %s \r\n", 
+                opResult.getIndex(), BytesValueEncoding.decode(opResult.getResult()));
+    }
+    
 
 ```

source/test/test-integration/src/test/java/test/com/jd/blockchain/intgr/IntegrationBase.java

@@ -25,6 +25,7 @@ import java.util.Random;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicLong;
 
+import com.jd.blockchain.ledger.*;
 import org.apache.commons.io.FileUtils;
 import org.springframework.core.io.ClassPathResource;
 
@@ -33,17 +34,6 @@ import com.jd.blockchain.contract.ReadContract;
 import com.jd.blockchain.crypto.AddressEncoding;
 import com.jd.blockchain.crypto.AsymmetricKeypair;
 import com.jd.blockchain.crypto.HashDigest;
-import com.jd.blockchain.ledger.BlockchainKeyGenerator;
-import com.jd.blockchain.ledger.BlockchainKeypair;
-import com.jd.blockchain.ledger.KVDataEntry;
-import com.jd.blockchain.ledger.LedgerBlock;
-import com.jd.blockchain.ledger.LedgerInitOperation;
-import com.jd.blockchain.ledger.OperationResult;
-import com.jd.blockchain.ledger.PreparedTransaction;
-import com.jd.blockchain.ledger.TransactionResponse;
-import com.jd.blockchain.ledger.TransactionState;
-import com.jd.blockchain.ledger.TransactionTemplate;
-import com.jd.blockchain.ledger.UserRegisterOperation;
 import com.jd.blockchain.ledger.core.LedgerRepository;
 import com.jd.blockchain.ledger.core.impl.LedgerManager;
 import com.jd.blockchain.sdk.BlockchainService;
@@ -609,6 +599,12 @@ public class IntegrationBase {
 		System.out.printf("readContract1.result = %s \r\n", result1.get());
 		System.out.printf("readContract3.result = %s \r\n", result3.get());
 
+		for (int i = 0; i < operationResults.length; i++) {
+			OperationResult opResult = operationResults[i];
+			System.out.printf("Operation[%s].result = %s \r\n", opResult.getIndex(), BytesValueEncoding.decode(opResult.getResult()));
+		}
+
+
 
 //		// 打印结果
 //		for (OperationResult or : operationResults) {