Add Cache to minidns

1 files changed, 46 insertions, 27 deletions

diff --git a/src/main/java/de/measite/minidns/Question.java b/src/main/java/de/measite/minidns/Question.java
index 9d1e3f56..8efe19f1 100644
--- a/src/main/java/de/measite/minidns/Question.java
+++ b/src/main/java/de/measite/minidns/Question.java
@@ -11,52 +11,71 @@ import de.measite.minidns.util.NameUtil;
 
 public class Question {
 
-    private String name;
+    private final String name;
 
-    private TYPE type;
+    private final TYPE type;
 
-    private CLASS clazz = CLASS.IN;
+    private final CLASS clazz;
 
-    public TYPE getType() {
-        return type;
-    }
+    private byte[] byteArray;
 
-    public void setType(TYPE type) {
+    public Question(String name, TYPE type, CLASS clazz) {
+        this.name = name;
         this.type = type;
+        this.clazz = clazz;
     }
 
-    public CLASS getClazz() {
-        return clazz;
+    public TYPE getType() {
+        return type;
     }
 
-    public void setClazz(CLASS clazz) {
-        this.clazz = clazz;
+    public CLASS getClazz() {
+        return clazz;
     }
 
     public String getName() {
         return name;
     }
 
-    public void setName(String name) {
-        this.name = name;
+    public static Question parse(DataInputStream dis, byte[] data) throws IOException {
+        String name = NameUtil.parse(dis, data);
+        TYPE type = TYPE.getType(dis.readUnsignedShort());
+        CLASS clazz = CLASS.getClass(dis.readUnsignedShort());
+        return new Question (name, type, clazz);
     }
 
-    public void parse(DataInputStream dis, byte[] data) throws IOException {
-        this.name = NameUtil.parse(dis, data);
-        this.type = TYPE.getType(dis.readUnsignedShort());
-        this.clazz = CLASS.getClass(dis.readUnsignedShort());
+    public byte[] toByteArray() {
+        if (byteArray == null) {
+            ByteArrayOutputStream baos = new ByteArrayOutputStream(512);
+            DataOutputStream dos = new DataOutputStream(baos);
+
+            try {
+                dos.write(NameUtil.toByteArray(this.name));
+                dos.writeShort(type.getValue());
+                dos.writeShort(clazz.getValue());
+                dos.flush();
+            } catch (IOException e) {
+                // Should never happen
+                throw new IllegalStateException(e);
+            }
+            byteArray = baos.toByteArray();
+        }
+        return byteArray;
     }
 
-    public byte[] toByteArray() throws IOException {
-        ByteArrayOutputStream baos = new ByteArrayOutputStream(512);
-        DataOutputStream dos = new DataOutputStream(baos);
-
-        dos.write(NameUtil.toByteArray(this.name));
-        dos.writeShort(type.getValue());
-        dos.writeShort(clazz.getValue());
-
-        dos.flush();
-        return baos.toByteArray();
+    @Override
+    public int hashCode() {
+        return toByteArray().hashCode();
     }
 
+    @Override
+    public boolean equals(Object other) {
+        if (this == other) {
+            return true;
+        }
+        if (!(other instanceof Question)) {
+            return false;
+        }
+        return this.hashCode() == other.hashCode();
+    }
 }