Upgrade to JUnit 4.12

The license has changed from Common Public License v1.0 to
Eclipse Public License v1.0.

This will not compile as it is because it is intended to be
built against Hamcrest 1.3 or later but it is being built
against Hamcrest 1.1.

A follow on patch will fix the compilation errors so that it
builds against Hamcrest 1.1. That allows Hamcrest to be upgraded
separately. The patch can be reverted once Hamcrest has been
upgraded.

There are also some Android specific issues that will also be
fixed in follow on patches.

Bug: 33613916
Test: make checkbuild
Change-Id: Ic2c983a030399e3ace1a14927cb143fbd8307b4f

1 files changed, 42 insertions, 0 deletions

diff --git a/src/main/java/org/junit/validator/AnnotationValidatorFactory.java b/src/main/java/org/junit/validator/AnnotationValidatorFactory.java
new file mode 100644
index 0000000..7309fdd
--- /dev/null
+++ b/src/main/java/org/junit/validator/AnnotationValidatorFactory.java
@@ -0,0 +1,42 @@
+package org.junit.validator;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Creates instances of Annotation Validators.
+ *
+ * @since 4.12
+ */
+public class AnnotationValidatorFactory {
+    private static final ConcurrentHashMap<ValidateWith, AnnotationValidator> VALIDATORS_FOR_ANNOTATION_TYPES =
+            new ConcurrentHashMap<ValidateWith, AnnotationValidator>();
+
+    /**
+     * Creates the AnnotationValidator specified by the value in
+     * {@link org.junit.validator.ValidateWith}. Instances are
+     * cached.
+     *
+     * @return An instance of the AnnotationValidator.
+     *
+     * @since 4.12
+     */
+    public AnnotationValidator createAnnotationValidator(ValidateWith validateWithAnnotation) {
+        AnnotationValidator validator = VALIDATORS_FOR_ANNOTATION_TYPES.get(validateWithAnnotation);
+        if (validator != null) {
+            return validator;
+        }
+
+        Class<? extends AnnotationValidator> clazz = validateWithAnnotation.value();
+        if (clazz == null) {
+            throw new IllegalArgumentException("Can't create validator, value is null in annotation " + validateWithAnnotation.getClass().getName());
+        }
+        try {
+            AnnotationValidator annotationValidator = clazz.newInstance();
+            VALIDATORS_FOR_ANNOTATION_TYPES.putIfAbsent(validateWithAnnotation, annotationValidator);
+            return VALIDATORS_FOR_ANNOTATION_TYPES.get(validateWithAnnotation);
+        } catch (Exception e) {
+            throw new RuntimeException("Exception received when creating AnnotationValidator class " + clazz.getName(), e);
+        }
+    }
+
+}