Use interface instead of implementations

src/main/java/com/wildbit/java/postmark/client/data/model/templates/BaseTemplatedMessage.java

@@ -7,10 +7,7 @@
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Paths;
-import java.util.ArrayList;
-import java.util.Base64;
-import java.util.HashMap;
-import java.util.Iterator;
+import java.util.*;
 
 /**
  * Base Template object.
@@ -26,8 +23,8 @@ public class BaseTemplatedMessage {
     private String bcc;
     private String replyTo;
     private String tag;
-    private ArrayList<Header> headers;
-    private ArrayList<HashMap<String, String>> attachments;
+    private List<Header> headers;
+    private List<Map<String, String>> attachments;
 
     public BaseTemplatedMessage() {
         this.setInlineCss(false);
@@ -66,11 +63,11 @@ public void setInlineCss(Boolean inlineCss) {
         this.inlineCss = inlineCss;
     }
 
-    public ArrayList<HashMap<String, String>> getAttachments() {
+    public List<Map<String, String>> getAttachments() {
         return attachments;
     }
 
-    public void setAttachments(ArrayList<HashMap<String, String>> attachments) {
+    public void setAttachments(List<Map<String, String>> attachments) {
         this.attachments = attachments;
     }
 
@@ -94,9 +91,9 @@ public void setTo(String to) {
      * Helper method for setting recipients with email address and their Full Name.
      *
      * @param to recipients list
-     * @see #convertRecipients(HashMap) for details
+     * @see #convertRecipients(Map) for details
      */
-    public void setTo(HashMap<String,String> to) {
+    public void setTo(Map<String,String> to) {
         this.to = convertRecipients(to);
     }
 
@@ -112,9 +109,9 @@ public void setCc(String cc) {
      * Helper method for setting recipients with email address and their Full Name.
      *
      * @param cc recipients list
-     * @see #convertRecipients(HashMap) for details
+     * @see #convertRecipients(Map) for details
      */
-    public void setCc(HashMap<String,String> cc) {
+    public void setCc(Map<String,String> cc) {
         this.cc = convertRecipients(cc);
     }
 
@@ -130,9 +127,9 @@ public void setBcc(String bcc) {
      * Helper method for setting recipients with email address and their Full Name.
      *
      * @param bcc recipients list
-     * @see #convertRecipients(HashMap) for details
+     * @see #convertRecipients(Map) for details
      */
-    public void setBcc(HashMap<String,String> bcc) {
+    public void setBcc(Map<String,String> bcc) {
         this.bcc = convertRecipients(bcc);
     }
 
@@ -152,11 +149,11 @@ public void setTag(String tag) {
         this.tag = tag;
     }
 
-    public ArrayList<Header> getHeaders() {
+    public List<Header> getHeaders() {
         return headers;
     }
 
-    public void setHeaders(ArrayList<Header> headers) {
+    public void setHeaders(List<Header> headers) {
         this.headers = headers;
     }
 
@@ -175,19 +172,19 @@ public void clearHeaders() {
 
 
     public void addAttachment(String path) throws IOException {
-        HashMap<String, String> attachment = new HashMap<>();
+        Map<String, String> attachment = new HashMap<>();
         attachment.put("Name", new File(path).getName());
         attachment.put("Content", readFileContent(path));
         attachment.put("ContentType", readFileContentType(path));
 
         addAttachment(attachment);
     }
 
-    public void addAttachment(HashMap<String, String> attachment) {
+    public void addAttachment(Map<String, String> attachment) {
         attachments.add(attachment);
     }
 
-    public void addAttachments(ArrayList<HashMap<String, String>> attachments) {
+    public void addAttachments(List<Map<String, String>> attachments) {
         attachments.forEach(this::addAttachment);
     }
 
@@ -204,18 +201,18 @@ private String readFileContentType(String path) {
 
     /**
      * This helper method allows setting list of recipients which will contain full name next to email address.
-     * By passing something like HashMap of: key -> John Smith, value -> [email protected]
+     * By passing something like Map of: key -> John Smith, value -> [email protected]
      * you would be able to send email to recipient John Smith ("John Smith" <[email protected]>)
      *
-     * @param recipients recipient hashmap, with Full Name, Email address pairs.
+     * @param recipients recipient map, with Full Name, Email address pairs.
      */
-    private String convertRecipients(HashMap<String,String> recipients) {
+    private String convertRecipients(Map<String,String> recipients) {
 
         StringBuilder recipientsString = new StringBuilder();
 
-        Iterator<HashMap.Entry<String, String>> entries = recipients.entrySet().iterator();
+        Iterator<Map.Entry<String, String>> entries = recipients.entrySet().iterator();
         while (entries.hasNext()) {
-            HashMap.Entry<String, String> entry = entries.next();
+            Map.Entry<String, String> entry = entries.next();
             recipientsString.append("\"").append(entry.getKey()).append("\"").append("<").append(entry.getValue()).append(">");
             if (entries.hasNext()) { recipientsString.append(","); }
         }