Add executable constaint

README.md

@@ -282,6 +282,20 @@ Makes sure a string contains a valid Java number.
     private File dir;
 ```
 
+### Executable
+
+```java
+    /**
+     * valid:
+     *      file.canExecute() == true
+     *
+     * invalid:
+     *      dir.canExecute() == false
+     */
+    @Executable
+    private File file;
+```
+
 ### Readable
 
 ```java

src/main/java/com/github/britter/beanvalidators/file/Executable.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2015 Benedikt Ritter
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.github.britter.beanvalidators.file;
+
+import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
+import static java.lang.annotation.ElementType.FIELD;
+import static java.lang.annotation.ElementType.METHOD;
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
+import javax.validation.Constraint;
+import javax.validation.Payload;
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+
+@Target({METHOD, FIELD, ANNOTATION_TYPE})
+@Retention(RUNTIME)
+@Constraint(validatedBy = ExecutableConstraintValidator.class)
+@Documented
+public @interface Executable {
+
+    String message() default "{com.github.britter.beanvalidators.io.Executable.message}";
+
+    Class<?>[] groups() default {};
+
+    Class<? extends Payload>[] payload() default {};
+
+}

src/main/java/com/github/britter/beanvalidators/file/ExecutableConstraintValidator.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2015 Benedikt Ritter
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.github.britter.beanvalidators.file;
+
+import javax.validation.ConstraintValidator;
+import javax.validation.ConstraintValidatorContext;
+import java.io.File;
+
+public class ExecutableConstraintValidator implements ConstraintValidator<Executable, File> {
+
+    @Override
+    public void initialize(Executable constraintAnnotation) {
+    }
+
+    @Override
+    public boolean isValid(File value, ConstraintValidatorContext context) {
+        return value == null || value.canExecute();
+    }
+
+}

src/main/resources/ValidationMessages.properties

@@ -4,6 +4,7 @@ com.github.britter.beanvalidators.io.Directory.message=must be a directory
 com.github.britter.beanvalidators.io.NotDirectory.message=must not be a directory
 com.github.britter.beanvalidators.io.Readable.message=must be readable
 com.github.britter.beanvalidators.io.Writable.message=must be writable
+com.github.britter.beanvalidators.io.Executable.message=must be executable
 
 com.github.britter.beanvalidators.net.Domain.message=must be a domain
 com.github.britter.beanvalidators.net.IP.message=must be an IP

src/test/java/com/github/britter/beanvalidators/file/ExecutableTest.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright 2015 Benedikt Ritter
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.github.britter.beanvalidators.file;
+
+import static com.google.common.collect.Iterables.getLast;
+import static org.hamcrest.Matchers.empty;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+import javax.validation.ConstraintViolation;
+import java.io.File;
+import java.util.Set;
+
+import com.github.britter.beanvalidators.ValidationWrapper;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+public class ExecutableTest {
+
+    private FileBean fileBean;
+    private ValidationWrapper<FileBean> validator;
+
+    @Rule
+    public TemporaryFolder tmpFolder = new TemporaryFolder();
+
+    @Before
+    public void setUp() {
+        fileBean = new FileBean();
+        validator = new ValidationWrapper<>(fileBean);
+    }
+
+    @Test
+    public void shouldValidateNull() throws Exception {
+        fileBean.file = null;
+
+        Set<ConstraintViolation<FileBean>> violations = validator.validate("file");
+
+        assertThat(violations, is(empty()));
+    }
+
+    @Test
+    public void shouldValidateExecutableDirectory() throws Exception {
+        fileBean.file = tmpFolder.newFolder();
+
+        Set<ConstraintViolation<FileBean>> violations = validator.validate("file");
+
+        assertThat(violations, is(empty()));
+    }
+
+    @Test
+    public void shouldValidateExecutableFile() throws Exception {
+        fileBean.file = tmpFolder.newFile();
+        fileBean.file.setExecutable(true);
+
+        Set<ConstraintViolation<FileBean>> violations = validator.validate("file");
+
+        assertThat(violations, is(empty()));
+    }
+
+    @Test
+    public void shouldNotValidateUnexecutableFile() throws Exception {
+        fileBean.file = new File("/should/not/exist");
+
+        Set<ConstraintViolation<FileBean>> violations = validator.validate("file");
+
+        assertThat(violations, hasSize(1));
+        ConstraintViolation<FileBean> violation = getLast(violations);
+        assertThat(violation.getMessage(), is(equalTo("must be executable")));
+    }
+
+    private static final class FileBean {
+        @Executable
+        private File file;
+    }
+}