feat($𝛌): support predicator's retryFunction

johnnymillergh · Oct 3, 2021 · b1c4a06 · b1c4a06
1 parent 194cdb8
commit b1c4a06
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Showing 2 changed files with 83 additions and 13 deletions.
diff --git a/spring-cloud-starter/src/main/java/com/jmsoftware/maf/springcloudstarter/function/Retry.java b/spring-cloud-starter/src/main/java/com/jmsoftware/maf/springcloudstarter/function/Retry.java
@@ -4,6 +4,10 @@
 import com.jmsoftware.maf.springcloudstarter.function.functionalinterface.ThrowExceptionFunction;
 import com.jmsoftware.maf.springcloudstarter.function.functionalinterface.ThrowExceptionRunnable;
 
+import java.util.function.BiFunction;
+import java.util.function.Function;
+import java.util.function.Predicate;
+
 /**
  * <h1>Retry</h1>
  * <p>
@@ -19,18 +23,18 @@ private Retry() {
     /**
      * Retry function.
      *
-     * @param runnable the runnable
-     * @param time     the time
+     * @param runnable  the runnable
+     * @param retryTime the retry time
      * @see com.jmsoftware.maf.springcloudstarter.FunctionalInterfaceTests#tesRetryFunction()
      */
-    public static void retryFunction(ThrowExceptionRunnable runnable, int time) {
+    public static void retryFunction(ThrowExceptionRunnable runnable, int retryTime) {
         while (true) {
             try {
                 runnable.run();
                 return;
             } catch (Exception e) {
-                time--;
-                if (time <= 0) {
+                retryTime--;
+                if (retryTime <= 0) {
                     throw new RuntimeException(e);
                 }
             }
@@ -40,26 +44,54 @@ public static void retryFunction(ThrowExceptionRunnable runnable, int time) {
     /**
      * Retry function r.
      *
-     * @param <T>      the type parameter
-     * @param <R>      the type parameter
-     * @param function the function
-     * @param t        the t
-     * @param time     the time
+     * @param <T>       the type parameter
+     * @param <R>       the type parameter
+     * @param function  the function
+     * @param t         the t
+     * @param retryTime the retry time
      * @return the r
      */
-    public static <T, R> R retryFunction(ThrowExceptionFunction<T, R> function, T t, int time) {
+    public static <T, R> R retryFunction(ThrowExceptionFunction<T, R> function, T t, int retryTime) {
         while (true) {
             try {
                 return function.apply(t);
             } catch (Exception e) {
-                time--;
-                if (time <= 0) {
+                retryTime--;
+                if (retryTime <= 0) {
                     throw new RuntimeException(e);
                 }
             }
         }
     }
 
+    /**
+     * Retry function r.
+     *
+     * @param <T>        the type parameter
+     * @param <R>        the type parameter
+     * @param function   the function
+     * @param t          the t
+     * @param predicator the predicator
+     * @param retryTime  the retry time
+     * @return the r
+     * @throws IllegalStateException the illegal state exception
+     * @see com.jmsoftware.maf.springcloudstarter.FunctionalInterfaceTests#tesRetryFunction()
+     */
+    public static <T, R> R retryFunction(Function<T, R> function, T t, Predicate<R> predicator, int retryTime
+    ) throws IllegalStateException {
+        while (retryTime > 0) {
+            try {
+                final var r = function.apply(t);
+                if (predicator.test(r)) {
+                    return r;
+                }
+            } finally {
+                retryTime--;
+            }
+        }
+        throw new IllegalStateException("retryTime reached hits the limit and the result is not correct");
+    }
+
     /**
      * Retry function r.
      *
@@ -84,4 +116,34 @@ public static <T, U, R> R retryFunction(ThrowExceptionBiFunction<T, U, R> functi
             }
         }
     }
+
+    /**
+     * Retry function r.
+     *
+     * @param <T>        the type parameter
+     * @param <U>        the type parameter
+     * @param <R>        the type parameter
+     * @param function   the function
+     * @param t          the t
+     * @param u          the u
+     * @param predicator the predicator
+     * @param retryTime  the retry time
+     * @return the r
+     * @throws IllegalStateException the illegal state exception
+     */
+    public static <T, U, R> R retryFunction(BiFunction<T, U, R> function, T t, U u, Predicate<R> predicator,
+                                            int retryTime
+    ) throws IllegalStateException {
+        while (retryTime > 0) {
+            try {
+                final var r = function.apply(t, u);
+                if (predicator.test(r)) {
+                    return r;
+                }
+            } finally {
+                retryTime--;
+            }
+        }
+        throw new IllegalStateException("retryTime reached hits the limit and the result is not correct");
+    }
 }
diff --git a/...starter/src/test/java/com/jmsoftware/maf/springcloudstarter/FunctionalInterfaceTests.java b/...starter/src/test/java/com/jmsoftware/maf/springcloudstarter/FunctionalInterfaceTests.java
@@ -140,5 +140,13 @@ void tesRetryFunction() {
             throw new IllegalStateException("Oops! Somehow, the code throws an exception");
         };
         Assertions.assertThrows(RuntimeException.class, () -> retryFunction(compute, 5));
+
+        final Function<Integer, Integer> compute2 = value -> 1 + value;
+        final var result = retryFunction(compute2, -1, integer -> integer.equals(0), 3);
+        Assertions.assertEquals(0, result);
+        Assertions.assertThrows(
+                IllegalStateException.class,
+                () -> retryFunction(compute2, 1, integer -> integer.equals(0), 3)
+        );
     }
 }