Allow type safe JSON parsing

Author: gesellix

engine/src/main/java/de/gesellix/docker/response/JsonChunksReader.java

@@ -8,24 +8,27 @@
 
 import java.io.IOException;
 
-public class JsonChunksReader implements Reader {
+public class JsonChunksReader<T> implements Reader<T> {
 
   private final JsonReader reader;
   private final Moshi moshi;
 
   public JsonChunksReader(Source source) {
-    moshi = new Moshi.Builder().add(new CustomObjectAdapterFactory()).build();
-    reader = JsonReader.of(Okio.buffer(source));
+    this(source, new Moshi.Builder().add(new CustomObjectAdapterFactory()).build());
+  }
 
+  public JsonChunksReader(Source source, Moshi moshi) {
+    this.moshi = moshi;
+    this.reader = JsonReader.of(Okio.buffer(source));
     // For transfer-encoding: chunked:
     // allows repeated `readNext` calls to consume
     // a complete stream of JSON chunks (delimited or not).
-    reader.setLenient(true);
+    this.reader.setLenient(true);
   }
 
   @Override
-  public Object readNext() throws IOException {
-    return moshi.adapter(Object.class).fromJson(reader);
+  public T readNext(Class<T> type) throws IOException {
+    return moshi.adapter(type).fromJson(reader);
 //    return reader.readJsonValue();
   }
 

engine/src/main/java/de/gesellix/docker/response/JsonContentHandler.java

@@ -25,9 +25,9 @@ private Object readJsonObject(InputStream stream) throws IOException {
 
   private Object readJsonObject(Source source) throws IOException {
     List<Object> parsed = new ArrayList<>();
-    JsonChunksReader reader = new JsonChunksReader(source);
+    JsonChunksReader<Object> reader = new JsonChunksReader<>(source);
     while (reader.hasNext()) {
-      parsed.add(reader.readNext());
+      parsed.add(reader.readNext(Object.class));
     }
 
     if (parsed.size() == 1) {

engine/src/main/java/de/gesellix/docker/response/LineReader.java

@@ -6,7 +6,7 @@
 
 import java.io.IOException;
 
-public class LineReader implements Reader {
+public class LineReader implements Reader<String> {
 
   private final BufferedSource buffer;
 
@@ -15,7 +15,7 @@ public LineReader(Source source) {
   }
 
   @Override
-  public Object readNext() throws IOException {
+  public String readNext(Class<String> type) throws IOException {
     return buffer.readUtf8Line();
   }
 

engine/src/main/java/de/gesellix/docker/response/Reader.java

@@ -2,9 +2,9 @@
 
 import java.io.IOException;
 
-public interface Reader {
+public interface Reader<T> {
 
-  Object readNext() throws IOException;
+  T readNext(Class<T> type) throws IOException;
 
   boolean hasNext() throws IOException;
 }