builder improvements

spring-security-rest-full/src/main/java/org/baeldung/persistence/dao/UserSpecificationsBuilder.java

@@ -8,40 +8,36 @@ import org.baeldung.web.util.SearchCriteria;
 import org.springframework.data.jpa.domain.Specification;
 import org.springframework.data.jpa.domain.Specifications;
 
-public class UserSpecificationsBuilder {
+public final class UserSpecificationsBuilder {
 
-    private List<SearchCriteria> params;
+    private final List<SearchCriteria> params;
 
     public UserSpecificationsBuilder() {
         params = new ArrayList<SearchCriteria>();
     }
 
-    public UserSpecificationsBuilder with(final String key, final String operation, final Object value) {
+    // API
-        final UserSpecificationsBuilder builder = new UserSpecificationsBuilder();
+
-        final List<SearchCriteria> newParams = new ArrayList<SearchCriteria>(params);
+    public final UserSpecificationsBuilder with(final String key, final String operation, final Object value) {
-        newParams.add(new SearchCriteria(key, operation, value));
+        params.add(new SearchCriteria(key, operation, value));
-        builder.params = newParams;
+        return this;
-        return builder;
     }
 
     public Specification<User> build() {
-        if (params.size() == 0)
+        if (params.size() == 0) {
             return null;
+        }
 
         final List<Specification<User>> specs = new ArrayList<Specification<User>>();
-
         for (final SearchCriteria param : params) {
             specs.add(new UserSpecification(param));
         }
 
-        if (specs.size() == 0)
-            return null;
-
         Specification<User> result = specs.get(0);
         for (int i = 1; i < specs.size(); i++) {
             result = Specifications.where(result).and(specs.get(i));
         }
         return result;
-
     }
+
 }

spring-security-rest-full/src/main/java/org/baeldung/web/controller/UserController.java

@@ -39,11 +39,12 @@ public class UserController {
         super();
     }
 
+    // API - READ
+
     @RequestMapping(method = RequestMethod.GET, value = "/users")
     @ResponseBody
     public List<User> findAll(@RequestParam(value = "search", required = false) final String search) {
         final List<SearchCriteria> params = new ArrayList<SearchCriteria>();
-
         if (search != null) {
             final Pattern pattern = Pattern.compile("(\\w+?)(:|<|>)(\\w+?),");
             final Matcher matcher = pattern.matcher(search + ",");
@@ -57,19 +58,15 @@ public class UserController {
     @RequestMapping(method = RequestMethod.GET, value = "/users/spec")
     @ResponseBody
     public List<User> findAllBySpecification(@RequestParam(value = "search") final String search) {
-        UserSpecificationsBuilder builder = new UserSpecificationsBuilder();
+        final UserSpecificationsBuilder builder = new UserSpecificationsBuilder();
-        if (search != null) {
+        final Pattern pattern = Pattern.compile("(\\w+?)(:|<|>)(\\w+?),");
-            final Pattern pattern = Pattern.compile("(\\w+?)(:|<|>)(\\w+?),");
+        final Matcher matcher = pattern.matcher(search + ",");
-            final Matcher matcher = pattern.matcher(search + ",");
+        while (matcher.find()) {
-            while (matcher.find()) {
+            builder.with(matcher.group(1), matcher.group(2), matcher.group(3));
-                builder = builder.with(matcher.group(1), matcher.group(2), matcher.group(3));
-            }
         }
+
         final Specification<User> spec = builder.build();
-        if (spec == null)
+        return dao.findAll(spec);
-            return dao.findAll();
-        else
-            return dao.findAll(spec);
     }
 
     @RequestMapping(method = RequestMethod.GET, value = "/myusers")
@@ -91,6 +88,8 @@ public class UserController {
             return mydao.findAll(exp);
     }
 
+    // API - WRITE
+
     @RequestMapping(method = RequestMethod.GET, value = "/users/new")
     @ResponseBody
     public long addUser(@RequestParam("first") final String first, @RequestParam("last") final String last, @RequestParam("age") final int age) {
@@ -114,4 +113,5 @@ public class UserController {
         mydao.save(user);
         return user.getId();
     }
+
 }