apache bval project (#1178)

* apache bval project

* update tests

* remove extra lines

apache-bval/src/main/java/com/baeldung/validation/Password.java

@@ -0,0 +1,25 @@
+package com.baeldung.validation;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import javax.validation.Constraint;
+import javax.validation.Payload;
+
+import static java.lang.annotation.ElementType.*;
+
+@Constraint(validatedBy = { PasswordValidator.class })
+@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
+@Retention(RetentionPolicy.RUNTIME)
+public @interface Password {
+    String message() default "Invalid password";
+
+    Class<?>[] groups() default {};
+
+    Class<? extends Payload>[] payload() default {};
+
+    int length() default 6;
+
+    int nonAlpha() default 1;
+}

apache-bval/src/main/java/com/baeldung/validation/PasswordValidator.java

@@ -0,0 +1,35 @@
+package com.baeldung.validation;
+
+import javax.validation.ConstraintValidator;
+import javax.validation.ConstraintValidatorContext;
+
+public class PasswordValidator implements ConstraintValidator<Password, String> {
+
+    private int length;
+    private int nonAlpha;
+
+    @Override
+    public void initialize(Password password) {
+        this.length = password.length();
+        this.nonAlpha = password.nonAlpha();
+
+    }
+
+    @Override
+    public boolean isValid(String value, ConstraintValidatorContext context) {
+        if (value.length() < length) {
+            return false;
+        }
+        int nonAlphaNr = 0;
+        for (int i = 0; i < value.length(); i++) {
+            if (!Character.isLetterOrDigit(value.charAt(i))) {
+                nonAlphaNr++;
+            }
+        }
+        if (nonAlphaNr < nonAlpha) {
+            return false;
+        }
+        return true;
+    }
+
+}