Merge pull request #1618 from sonatype/constraint-violation-factory

ConstraintViolationFactory

components/nexus-validation/src/main/java/org/sonatype/nexus/validation/ConstraintViolationFactory.java

@@ -0,0 +1,137 @@
+/*
+ * Sonatype Nexus (TM) Open Source Version
+ * Copyright (c) 2008-present Sonatype, Inc.
+ * All rights reserved. Includes the third-party code listed at http://links.sonatype.com/products/nexus/oss/attributions.
+ *
+ * This program and the accompanying materials are made available under the terms of the Eclipse Public License Version 1.0,
+ * which accompanies this distribution and is available at http://www.eclipse.org/legal/epl-v10.html.
+ *
+ * Sonatype Nexus (TM) Professional Version is available from Sonatype, Inc. "Sonatype" and "Sonatype Nexus" are trademarks
+ * of Sonatype, Inc. Apache Maven is a trademark of the Apache Software Foundation. M2eclipse is a trademark of the
+ * Eclipse Foundation. All other trademarks are the property of their respective owners.
+ */
+package org.sonatype.nexus.validation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+
+import javax.inject.Inject;
+import javax.inject.Named;
+import javax.inject.Provider;
+import javax.inject.Singleton;
+import javax.validation.Constraint;
+import javax.validation.ConstraintValidatorContext;
+import javax.validation.ConstraintValidatorContext.ConstraintViolationBuilder;
+import javax.validation.ConstraintValidatorContext.ConstraintViolationBuilder.NodeBuilderCustomizableContext;
+import javax.validation.ConstraintViolation;
+import javax.validation.Payload;
+import javax.validation.Validator;
+
+import org.sonatype.sisu.goodies.common.ComponentSupport;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static java.lang.annotation.ElementType.TYPE;
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
+/**
+ * Factory of {@link ConstraintViolation}s to be used (rarely) for manual validation.
+ *
+ * @since 3.0
+ */
+@Named
+@Singleton
+public class ConstraintViolationFactory
+    extends ComponentSupport
+{
+  private final Provider<Validator> validatorProvider;
+
+  @Inject
+  public ConstraintViolationFactory(final Provider<Validator> validatorProvider) {
+    this.validatorProvider = checkNotNull(validatorProvider);
+  }
+
+  /**
+   * Create a violation with specified path and message.
+   *
+   * @param path    violation path
+   * @param message violation message
+   * @return created violation
+   */
+  public ConstraintViolation<?> createViolation(final String path, final String message) {
+    checkNotNull(path);
+    checkNotNull(message);
+    return validatorProvider.get().validate(new HelperBean(path, message)).iterator().next();
+  }
+
+  /**
+   * Bean passing path/message.
+   */
+  @HelperAnnotation
+  private static class HelperBean
+  {
+    private final String path;
+
+    private final String message;
+
+    public HelperBean(final String path, final String message) {
+      this.path = path;
+      this.message = message;
+    }
+
+    public String getPath() {
+      return path;
+    }
+
+    public String getMessage() {
+      return message;
+    }
+  }
+
+  /**
+   * Annotation to trigger validation.
+   *
+   * @since 3.0
+   */
+  @Target({TYPE})
+  @Retention(RUNTIME)
+  @Constraint(validatedBy = HelperValidator.class)
+  @Documented
+  private @interface HelperAnnotation
+  {
+    String message() default "";
+
+    Class<?>[] groups() default {};
+
+    Class<? extends Payload>[] payload() default {};
+  }
+
+  /**
+   * {@link HelperAnnotation} validator.
+   */
+  private static class HelperValidator
+      extends ConstraintValidatorSupport<HelperAnnotation, HelperBean>
+  {
+    @Override
+    public boolean isValid(final HelperBean bean, final ConstraintValidatorContext context) {
+      context.disableDefaultConstraintViolation();
+
+      // build a custom property path
+      ConstraintViolationBuilder builder = context.buildConstraintViolationWithTemplate(bean.getMessage());
+      NodeBuilderCustomizableContext nodeBuilder = null;
+      for (String part : bean.getPath().split("\\.")) {
+        if (nodeBuilder == null) {
+          nodeBuilder = builder.addPropertyNode(part);
+        }
+        else {
+          nodeBuilder = nodeBuilder.addPropertyNode(part);
+        }
+      }
+      if (nodeBuilder != null) {
+        nodeBuilder.addConstraintViolation();
+      }
+
+      return false;
+    }
+  }
+}