Java合约

预备知识

XuperChain 基本操作

注解

请先完成 XuperChain 基本操作 中的教程，以确设置对应账号和权限

1.合约样例

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
package com.baidu.xuper.example;

import java.math.BigInteger;

import com.baidu.xuper.Context;
import com.baidu.xuper.Contract;
import com.baidu.xuper.ContractMethod;
import com.baidu.xuper.Driver;
import com.baidu.xuper.Response;

/**
* Counter
*/
public class Counter implements Contract {

    @Override
    @ContractMethod
    public Response initialize(Context ctx) {
        return Response.ok("ok".getBytes());
    }

    @ContractMethod
    public Response increase(Context ctx) {
        byte[] key = ctx.args().get("key");
        if (key == null) {
            return Response.error("missing key");
        }
        BigInteger counter;
        byte[] value = ctx.getObject(key);
        if (value != null) {
            counter = new BigInteger(value);
        } else {
            ctx.log("key " + new String(key) + " not found, initialize to zero");
            counter = BigInteger.valueOf(0);
        }
        ctx.log("get value " + counter.toString());
        counter = counter.add(BigInteger.valueOf(1));
        ctx.putObject(key, counter.toByteArray());

        return Response.ok(counter.toString().getBytes());
    }

    @ContractMethod
    public Response get(Context ctx) {
        byte[] key = ctx.args().get("key");
        if (key == null) {
            return Response.error("missing key");
        }
        BigInteger counter;
        byte[] value = ctx.getObject(key);
        if (value != null) {
            counter = new BigInteger(value);
        } else {
            return Response.error("key " + new String(key) + " not found)");
        }
        ctx.log("get value " + counter.toString());

        return Response.ok(counter.toString().getBytes());
    }

    public static void main(String[] args) {
        Driver.serve(new Counter());
    }
}

2.合约编译

cd contractsdk/java/example/counter
mvn package -f pom.xml
# 产出二进制文件target/counter-0.1.0-jar-with-dependencies.jar，用于合约部署

3.合约部署

xchain-cli native deploy --account XC1111111111111111@xuper --fee 15587517 --runtime java targets/counter-0.1.0-jar-with-dependencies.jar --cname counter

4. 合约调用

$ xchain-cli native invoke --method increase -a '{"key":"test"}' counter --fee 10
 contract response: 1
 The gas you cousume is: 6
 The fee you pay is: 10
 Tx id: 4b46d9b1292481dcac3b504d5f8031e4eff44d8514c9508f121145cfa141d9db

$ xchain-cli native query --method get -a '{"key":"test"}' counter
contract response: 1146398290725d36631aa70f731bc3174e6484a9a