ThreadLocal应用-使用ThreadLocal做线程缓存变量池

多线程环境下，或者web环境下，可以使用ThreadLocal做变量池用


import java.util.HashMap;
import java.util.Map;public abstract class AbstractThreadContext {public AbstractThreadContext() {}abstract ThreadLocal<Map<String, Object>> getThreadContext();public void set(final String key, final Object value) {ThreadLocal<Map<String, Object>> threadContext = this.getThreadContext();Map<String, Object> map = (Map)threadContext.get();if (map == null) {map = new HashMap();}((Map)map).put(key, value);threadContext.set(map);}public void removeKey(String key) {ThreadLocal<Map<String, Object>> threadContext = this.getThreadContext();Map<String, Object> map = (Map)threadContext.get();if (map == null) {map = new HashMap();}((Map)map).remove(key);threadContext.set(map);}public Object get(String key) {ThreadLocal<Map<String, Object>> threadContext = this.getThreadContext();Map<String, Object> map = (Map)threadContext.get();return map == null ? null : map.get(key);}public void clean() {ThreadLocal<Map<String, Object>> threadContext = this.getThreadContext();Map<String, Object> map = (Map)threadContext.get();if (map != null) {map.clear();threadContext.set(map);}}
}


import java.util.Map;public final class ThreadContextStoreUtil extends AbstractThreadContext {private static ThreadLocal<Map<String, Object>> threadContext = new ThreadLocal();private static volatile ThreadContextStoreUtil app = null;private ThreadContextStoreUtil() {}public static synchronized ThreadContextStoreUtil getInstance() {if (app == null) {Class var0 = ThreadContextStoreUtil.class;synchronized(ThreadContextStoreUtil.class) {if (app == null) {app = new ThreadContextStoreUtil();}}}return app;}@Overrideprotected ThreadLocal<Map<String, Object>> getThreadContext() {return threadContext;}
}


public class ThreadMain {public static void main(String[] args) {new Thread(new Runnable() {@Overridepublic void run() {ThreadContextStoreUtil.getInstance().set("1", "1");ThreadContextStoreUtil.getInstance().set("2", "11");ThreadContextStoreUtil.getInstance().set("3", "111");System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("1"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("2"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("3"));}}, "a").start();new Thread(new Runnable() {@Overridepublic void run() {ThreadContextStoreUtil.getInstance().set("1", "2");ThreadContextStoreUtil.getInstance().set("2", "22");ThreadContextStoreUtil.getInstance().set("3", "222");System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("1"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("2"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("3"));}}, "b").start();new Thread(new Runnable() {@Overridepublic void run() {ThreadContextStoreUtil.getInstance().set("1", "3");ThreadContextStoreUtil.getInstance().set("2", "33");ThreadContextStoreUtil.getInstance().set("3", "333");System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("1"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("2"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("3"));}}, "c").start();new Thread(new Runnable() {@Overridepublic void run() {ThreadContextStoreUtil.getInstance().set("1", "4");ThreadContextStoreUtil.getInstance().set("2", "44");ThreadContextStoreUtil.getInstance().set("3", "444");System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("1"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("2"));System.out.println(Thread.currentThread().getName() + ThreadContextStoreUtil.getInstance().get("3"));}}, "d").start();}
}

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ThreadLocal应用-使用ThreadLocal做线程缓存变量池

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