init

src/main/java/com/eactive/eai/common/state/ElinkState.java

@@ -0,0 +1,8 @@
+package com.eactive.eai.common.state;
+
+public enum ElinkState {
+    STARTING,
+    STARTED,
+    STOPPING,
+    STOPPED
+}

src/main/java/com/eactive/eai/common/state/ElinkStateException.java

@@ -0,0 +1,17 @@
+package com.eactive.eai.common.state;
+
+public class ElinkStateException extends Exception {
+	private static final long serialVersionUID = 1L;
+
+	public ElinkStateException(String msg) {
+		super(msg);
+	}
+
+	public ElinkStateException(Throwable cause) {
+		super(cause);
+	}
+
+	public ElinkStateException(String msg, Throwable cause) {
+		super(msg, cause);
+	}
+}

src/main/java/com/eactive/eai/common/state/ElinkStateManager.java

@@ -0,0 +1,122 @@
+package com.eactive.eai.common.state;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+import com.eactive.eai.common.util.DatetimeUtil;
+import com.eactive.eai.common.util.Logger;
+
+public class ElinkStateManager {
+	private static ElinkStateManager instance;
+	private volatile ElinkState currentState = ElinkState.STOPPED;
+	private AtomicInteger transactionsInProgress = new AtomicInteger(0);
+	private long waitMaxMs = 60000;
+	private long sleepIntervalMs = 500;
+
+	private static final String LOG_PREFIX = "ElinkStateManager] ";
+
+	private void log(String message) {
+		Logger logger = Logger.getLogger(Logger.LOGGER_DEFAULT);
+		if (logger != null) {
+			logger.warn(message);
+		}
+		System.out.println(DatetimeUtil.getCurrentTime() + " " + LOG_PREFIX + message);
+	}
+
+	public static synchronized ElinkStateManager getInstance() {
+		if (instance == null) {
+			instance = new ElinkStateManager();
+		}
+		return instance;
+	}
+
+	public int getTransactionsInProgress() {
+		return transactionsInProgress.get();
+	}
+
+	public long getWaitMaxMs() {
+		return waitMaxMs;
+	}
+
+	public void setWaitMaxMs(long waitMaxMs) {
+		this.waitMaxMs = waitMaxMs;
+	}
+	
+	public long getSleepIntervalMs() {
+		return sleepIntervalMs;
+	}
+
+	public void setSleepIntervalMs(long sleepIntervalMs) {
+		this.sleepIntervalMs = sleepIntervalMs;
+	}
+
+	public void starting() {
+		synchronized (this) {
+			if (currentState == ElinkState.STOPPED) {
+				currentState = ElinkState.STARTING;
+				log("Elink starting successfully.");
+			} else {
+				log("Elink is already started or in the process of starting.");
+			}
+		}
+	}
+
+	public void started() {
+		synchronized (this) {
+			if (currentState == ElinkState.STARTING) {
+				currentState = ElinkState.STARTED;
+				log("Elink started successfully.");
+			} else {
+				log("Elink is already started or in the process of started.");
+			}
+		}
+	}
+
+	public void stop() {
+		if (this.waitMaxMs <= 0) {
+			log("Elink stopping - transactionsInProgress : " + transactionsInProgress.get() + " waitMaxMs : "
+					+ this.waitMaxMs + " sleepIntervalMs : " + this.sleepIntervalMs);
+			currentState = ElinkState.STOPPED;
+			log("Elink stopped forcely.");
+			return;
+		}
+
+		log("Elink stopping - transactionsInProgress : " + transactionsInProgress.get() + " waitMaxMs : "
+				+ this.waitMaxMs);
+
+		if (currentState == ElinkState.STARTED || currentState == ElinkState.STARTING) {
+			currentState = ElinkState.STOPPING;
+			long startTime = System.currentTimeMillis();
+			while (transactionsInProgress.get() > 0) {
+				long elapsedTime = System.currentTimeMillis() - startTime;
+				if (elapsedTime >= waitMaxMs) {
+					log("Timeout! Unable to stop. Transactions are still in progress. transactionsInProgress: "
+							+ transactionsInProgress.get());
+					break;
+				}
+				try {
+					log("Elink wait in procress transaction, sleep " + sleepIntervalMs
+							+ " msecs. transactionsInProgress : " + transactionsInProgress.get());
+					Thread.sleep(sleepIntervalMs);
+				} catch (InterruptedException e) {
+					e.printStackTrace();
+				}
+			}
+			currentState = ElinkState.STOPPED;
+			log("Elink stopped successfully.");
+		} else {
+			log("Elink is already stopped or in the process of stopping.");
+		}
+	}
+
+	public void startRequest() {
+		transactionsInProgress.incrementAndGet();
+	}
+
+	public void completeRequest() {
+		transactionsInProgress.decrementAndGet();
+	}
+
+	public ElinkState getState() {
+		return currentState;
+	}
+}