Allow null body in response entity and persistent client true or false (#15)

* Allow null body in response entity

* HttpRequest can be set to use a persistent/singleton client or a new one

Author: Christoffer-Cortes

src/main/java/com/ericsson/eiffelcommons/utils/HttpExecutor.java

@@ -30,7 +30,7 @@ public final class HttpExecutor {
     private CloseableHttpClient client = HttpClientBuilder.create()
                                                           .build();
 
-    private HttpExecutor() {
+    public HttpExecutor() {
 
     }
 

src/main/java/com/ericsson/eiffelcommons/utils/HttpRequest.java

@@ -41,7 +41,7 @@
 public class HttpRequest {
 
     private HttpRequestBase request;
-    private HttpExecutor executor = HttpExecutor.getInstance();
+    private HttpExecutor executor;
 
     public enum HttpMethod {
         GET, POST, DELETE, PUT
@@ -57,6 +57,10 @@ public enum HttpMethod {
     protected Map<String, String> params;
 
     public HttpRequest(HttpMethod method) {
+        this(method, false);
+    }
+
+    public HttpRequest(HttpMethod method, boolean persistentClient) {
         params = new HashMap<>();
 
         switch (method) {
@@ -73,6 +77,16 @@ public HttpRequest(HttpMethod method) {
                 request = new HttpPut();
                 break;
         }
+
+        initExecutor(persistentClient);
+    }
+
+    private void initExecutor(boolean persistentClient) {
+        if(persistentClient) {
+            executor = HttpExecutor.getInstance();
+        } else {
+            executor = new HttpExecutor();
+        }
     }
 
     /**

src/main/java/com/ericsson/eiffelcommons/utils/ResponseEntity.java

@@ -29,7 +29,7 @@
 public class ResponseEntity {
 
     private int statusCode;
-    private String body;
+    private String body = "";
     private Header[] headers;
 
     /**
@@ -42,7 +42,9 @@ public class ResponseEntity {
     public ResponseEntity(HttpResponse httpResponse) throws ParseException, IOException {
         this.statusCode = httpResponse.getStatusLine()
                                       .getStatusCode();
-        this.body = EntityUtils.toString(httpResponse.getEntity(), "utf-8");
+        if(httpResponse.getEntity() != null) {
+            this.body = EntityUtils.toString(httpResponse.getEntity(), "utf-8");
+        }
         this.headers = httpResponse.getAllHeaders();
     }