feat: 新增断路状态管理器.

src/main/java/com/serliunx/statemanagement/manager/BreakageUnidirectionalStateManager.java

@@ -0,0 +1,90 @@
+package com.serliunx.statemanagement.manager;
+
+import com.serliunx.statemanagement.exception.StateException;
+
+import java.util.List;
+
+/**
+ * 断路的单向状态管理器
+ * <p> 逻辑与{@link UnidirectionalStateManager}大体相同, 不同的点在于:
+ * <li> 最后一个状态无法转向第一个状态, 即为一次性的状态管理器.
+ *
+ * @author <a href="mailto:serliunx@yeah.net">SerLiunx</a>
+ * @version 1.0.0
+ * @since 2025/1/13
+ */
+public final class BreakageUnidirectionalStateManager<S> extends DefaultUnidirectionalStateManager<S> {
+
+    /**
+     * 是否在切换失败时抛出异常
+     */
+    private final boolean allowThrow;
+
+    public BreakageUnidirectionalStateManager(List<S> stateList, boolean allowThrow) {
+        super(stateList);
+        this.allowThrow = allowThrow;
+    }
+
+    public BreakageUnidirectionalStateManager(S[] states, boolean allowThrow) {
+        super(states);
+        this.allowThrow = allowThrow;
+    }
+
+    public BreakageUnidirectionalStateManager(List<S> stateList) {
+        this(stateList, true);
+    }
+
+    public BreakageUnidirectionalStateManager(S[] states) {
+        this(states, true);
+    }
+
+    @Override
+    public S switchNextAndGet() {
+        if (isLast()) {
+            if (allowThrow)
+                throw new StateException("The last state has been reached and cannot be switched again!");
+            return null;
+        }
+        return super.switchNextAndGet();
+    }
+
+    @Override
+    public S getAndSwitchNext() {
+        if (isLast()) {
+            if (allowThrow)
+                throw new StateException("The last state has been reached and cannot be switched again!");
+            return null;
+        }
+        return super.getAndSwitchNext();
+    }
+
+    @Override
+    public void switchNext() {
+        if (isLast()) {
+            if (allowThrow)
+                throw new StateException("The last state has been reached and cannot be switched again!");
+            return;
+        }
+        super.switchNext();
+    }
+
+    @Override
+    public boolean switchTo(S state) {
+        if (isLast()) {
+            if (allowThrow)
+                throw new StateException("The last state has been reached and cannot be switched again!");
+            return false;
+        }
+        return super.switchTo(state);
+    }
+
+    @Override
+    public boolean isCircle() {
+        return false;
+    }
+
+    @Override
+    public void reset() {
+        throw new UnsupportedOperationException("Cannot reset state for BreakageUnidirectionalStateManager!");
+    }
+}

src/main/java/com/serliunx/statemanagement/manager/CircleStateManager.java

@@ -0,0 +1,21 @@
+package com.serliunx.statemanagement.manager;
+
+/**
+ * 将指定状态管理器标记为循环的状态管理器
+ * <li> 允许单向、双向循环
+ *
+ * @author <a href="mailto:serliunx@yeah.net">SerLiunx</a>
+ * @version 1.0.0
+ * @since 2025/1/13
+ */
+public interface CircleStateManager {
+
+    /**
+     * 是否为循环的状态管理器
+     *
+     * @return 属于循环状态管理器返回真, 否则返回假.
+     */
+    default boolean isCircle() {
+        return true;
+    }
+}

src/main/java/com/serliunx/statemanagement/manager/UnidirectionalStateManager.java

@@ -17,7 +17,7 @@ package com.serliunx.statemanagement.manager;
  * @version 1.0.0
  * @since 2024/12/28
  */
-public interface UnidirectionalStateManager<S> extends StateManager<S> {
+public interface UnidirectionalStateManager<S> extends StateManager<S>, CircleStateManager {
 
 	/**
 	 * 切换至下一个状态并返回切换后的状态

src/test/java/com/serliunx/statemanagement/ManagerTest.java

@@ -1,5 +1,6 @@
 package com.serliunx.statemanagement;
 
+import com.serliunx.statemanagement.manager.BreakageUnidirectionalStateManager;
 import com.serliunx.statemanagement.manager.DefaultUnidirectionalStateManager;
 import com.serliunx.statemanagement.manager.UnidirectionalStateManager;
 import com.serliunx.statemanagement.support.PrinterState;
@@ -24,4 +25,11 @@ public class ManagerTest {
 		System.out.println(unidirectionalStateManager.switchTo(PrinterState.IDLE));
 		System.out.println(unidirectionalStateManager.switchTo(PrinterState.SCANNING));
 	}
+
+	@Test
+	public void testBreakageUnidirectionalStateManager() {
+		UnidirectionalStateManager<PrinterState> bum = new BreakageUnidirectionalStateManager<>(PrinterState.values());
+		System.out.println(bum.isCircle());
+		bum.switchNext();
+	}
 }