启动一个Ignite实例
bin/ignite.sh
[17:10:44] Ignite node started OK (id=c44bebb1)
[17:10:44] Topology snapshot [ver=1, servers=1, clients=0, CPUs=4, heap=1.8GB]
创建maven工程，并加入相关依赖
<properties>
<ignite.version>2.2.0</ignite.version>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-core</artifactId>
<version>${ignite.version}</version>
</dependency>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-spring</artifactId>
<version>${ignite.version}</version>
</dependency>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-indexing</artifactId>
<version>${ignite.version}</version>
</dependency>
</dependencies>
创建Data Grid应用FirstCacheDemo
public class FirstCacheDemo {
public static void main(String[] args) throws IgniteException {
Ignite ignite = Ignition.start();
IgniteCache<Integer, Object> cache = ignite.getOrCreateCache("c1");
cache.clear();
int keyCnt = 10;
System.out.println("Synchronously put records ...");
for (int i = 0; i < keyCnt; i++)
cache.put(i, Integer.toString(i));
for (int i = 0; i < keyCnt; i++)
System.out.println("Got [key=" + i + ", val=" + cache.get(i) + "] ");
}
}
运行后输出为
[17:18:48] Ignite node started OK (id=0957a691)
[17:18:48] Topology snapshot [ver=12, servers=2, clients=0, CPUs=4, heap=3.6GB]
Synchronously put records ...
Got [key=0, val=0]
Got [key=1, val=1]
Got [key=2, val=2]
Got [key=3, val=3]
Got [key=4, val=4]
Got [key=5, val=5]
Got [key=6, val=6]
Got [key=7, val=7]
Got [key=8, val=8]
Got [key=9, val=9]
可以看出，put 是一个同步方法，其相对应的异步方法为 putAsync， 这也是Ignite大多数异步方法的命名规则。 我们将 put 改为 putAsync
System.out.println("Asynchronously put records ...");
for (int i = 0; i < keyCnt; i++)
cache.putAsync(i, Integer.toString(i));
for (int i = 0; i < keyCnt; i++)
System.out.println("Got [key=" + i + ", val=" + cache.get(i) + "] ");
输出结果为
Asynchronously put records ...
Got [key=0, val=null]
Got [key=1, val=1]
Got [key=2, val=2]
Got [key=3, val=3]
Got [key=4, val=4]
Got [key=5, val=5]
Got [key=6, val=6]
Got [key=7, val=7]
Got [key=8, val=8]
Got [key=9, val=9]
可以看出，简单的 get 方法不能保证数据能正常读出，需要配合使用 IgniteFuture，等待所有 future 结束。
System.out.println("Asynchronously put records ...");
Collection<IgniteFuture<?>> futs = new ArrayList<>();
for (int i = 0; i < keyCnt; i++)
futs.add(cache.putAsync(i, Integer.toString(i)));
// Wait for completion of all futures.
for (IgniteFuture<?> fut : futs)
fut.get();
for (int i = 0; i < keyCnt; i++)
System.out.println("Got [key=" + i + ", val=" + cache.get(i) + "] ");
在执行就一切正常了
Asynchronously put records ...
Got [key=0, val=0]
Got [key=1, val=1]
Got [key=2, val=2]
Got [key=3, val=3]
Got [key=4, val=4]
Got [key=5, val=5]
Got [key=6, val=6]
Got [key=7, val=7]
Got [key=8, val=8]
Got [key=9, val=9]
Configure Ignite
之前我们使用了Ignite的默认配置，直接调用 Ignition.start() 就启动了实例，同样我们可以对所启动的实例做特殊配置，一般有两种方法
- 通过code进行配置
TcpDiscoverySpi spi = new TcpDiscoverySpi();
TcpDiscoveryVmIpFinder ipFinder = new TcpDiscoveryVmIpFinder();
ipFinder.setAddresses(Arrays.asList("10.xxx.xxx.xxx:47500..47509"));
spi.setIpFinder(ipFinder);
IgniteConfiguration cfg = new IgniteConfiguration();
cfg.setDiscoverySpi(spi);
// Enable client mode.
cfg.setClientMode(true);
Ignite ignite = Ignition.start(cfg);
- 通过配置文件导入
Ignite ignite = Ignition.start("config/xxx.xml");
直接这么写会出错，网上有人说在IDE里需要设置JVM变量 -DIGNITE_HOME 即可，但仍然失败， 最终发现如下写法是OK的
Ignite ignite = Ignition.start("file:///D:\Work\ignitedemo\resource\example-cache.xml");
至此，一个比较完整的First Data Grid应用就算是OK了。
