Add ordering to entity converters, and made the manager immutable.

http-requests-core/src/main/java/com/budjb/httprequests/Ordered.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2016-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.budjb.httprequests;
+
+public interface Ordered {
+    /**
+     * Default priority.
+     */
+    int DEFAULT_PRIORITY = 0;
+
+    /**
+     * Lowest priority.
+     */
+    int LOWEST_PRIORITY = Integer.MIN_VALUE;
+
+    /**
+     * Highest priority.
+     */
+    int HIGHEST_PRIORITY = Integer.MAX_VALUE;
+
+    /**
+     * Returns an order used for comparison and sorting.
+     *
+     * @return An order used for comparison and sorting.
+     */
+    default int getOrder() {
+        return DEFAULT_PRIORITY;
+    }
+}

http-requests-core/src/main/java/com/budjb/httprequests/converter/EntityConverterManager.java

@@ -17,13 +17,14 @@
 
 import com.budjb.httprequests.ConvertingHttpEntity;
 import com.budjb.httprequests.HttpEntity;
+import com.budjb.httprequests.Ordered;
 import com.budjb.httprequests.exception.UnsupportedConversionException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -36,15 +37,17 @@ public class EntityConverterManager {
     /**
      * List of registered entity converters.
      */
-    private final List<EntityConverter> converters = new ArrayList<>();
+    private final List<EntityConverter> converters;
 
-    /**
-     * Adds an entity converter to the manager.
-     *
-     * @param converter Converter to add to the manager.
-     */
-    public void add(EntityConverter converter) {
-        converters.add(converter);
+    public EntityConverterManager(List<EntityConverter> entityConverters) {
+        Comparator<EntityConverter> comparator = (o1, o2) -> {
+            int l = (o1 instanceof Ordered) ? ((Ordered) o1).getOrder() : 0;
+            int r = (o2 instanceof Ordered) ? ((Ordered) o2).getOrder() : 0;
+
+            return Integer.compare(r, l);
+        };
+
+        converters = entityConverters.stream().sorted(comparator).collect(Collectors.toList());
     }
 
     /**
@@ -56,22 +59,6 @@ public List<EntityConverter> getAll() {
         return converters;
     }
 
-    /**
-     * Remove an entity converter.
-     *
-     * @param converter Entity converter to remove.
-     */
-    public void remove(EntityConverter converter) {
-        converters.remove(converter);
-    }
-
-    /**
-     * Remove all entity converters.
-     */
-    public void clear() {
-        converters.clear();
-    }
-
     /**
      * Returns the list of all registered entity readers.
      *

http-requests-core/src/main/java/com/budjb/httprequests/converter/bundled/StringEntityReader.java

@@ -15,6 +15,7 @@
  */
 package com.budjb.httprequests.converter.bundled;
 
+import com.budjb.httprequests.Ordered;
 import com.budjb.httprequests.StreamUtils;
 import com.budjb.httprequests.converter.EntityReader;
 
@@ -24,7 +25,7 @@
 /**
  * An entity reader that converts an entity into a String. The character set of the entity is respected.
  */
-public class StringEntityReader implements EntityReader {
+public class StringEntityReader implements EntityReader, Ordered {
     /**
      * Determines if the reader supports converting an entity to the given class type.
      *
@@ -55,4 +56,12 @@ public Object read(InputStream entity, String contentType, String charset) throw
 
         return StreamUtils.readString(entity, charset);
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public int getOrder() {
+        return Ordered.LOWEST_PRIORITY + 10;
+    }
 }

http-requests-core/src/main/java/com/budjb/httprequests/converter/bundled/StringEntityWriter.java

@@ -15,6 +15,7 @@
  */
 package com.budjb.httprequests.converter.bundled;
 
+import com.budjb.httprequests.Ordered;
 import com.budjb.httprequests.converter.EntityWriter;
 
 import java.io.ByteArrayInputStream;
@@ -24,7 +25,7 @@
 /**
  * An entity writer that converts a String.
  */
-public class StringEntityWriter implements EntityWriter {
+public class StringEntityWriter implements EntityWriter, Ordered {
     /**
      * Returns a Content-Type of the converted object that will be set in the HTTP request.
      * <p>
@@ -66,4 +67,12 @@ public InputStream write(Object entity, String characterSet) throws Exception {
 
         return new ByteArrayInputStream(((String) entity).getBytes(characterSet));
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public int getOrder() {
+        return Ordered.LOWEST_PRIORITY + 10;
+    }
 }

http-requests-core/src/test/groovy/com/budjb/httprequests/HttpResponseExceptionSpec.groovy

@@ -26,7 +26,7 @@ class HttpResponseExceptionSpec extends Specification {
     def 'When an HttpResponseException is build with status #status, exception type #type is returned'() {
         setup:
         HttpResponse response = new MockHttpResponse(
-            new EntityConverterManager(),
+            new EntityConverterManager([]),
             new HttpRequest(),
             status,
             new MultiValuedMap(),

http-requests-core/src/test/groovy/com/budjb/httprequests/HttpResponseSpec.groovy

@@ -23,8 +23,7 @@ import spock.lang.Specification
 class HttpResponseSpec extends Specification {
     def 'When a charset is provided, the resulting string is built using it'() {
         setup:
-        EntityConverterManager converterManager = new EntityConverterManager()
-        converterManager.add(new StringEntityReader())
+        EntityConverterManager converterManager = new EntityConverterManager([new StringEntityReader()])
 
         HttpEntity httpEntity = new HttpEntity(new ByteArrayInputStream('åäö'.getBytes()), 'text/plain', 'euc-jp')
         HttpResponse response = new MockHttpResponse(
@@ -50,7 +49,7 @@ class HttpResponseSpec extends Specification {
         headers.add("peek", "boo")
 
         HttpResponse response = new MockHttpResponse(
-            new EntityConverterManager(),
+            new EntityConverterManager([]),
             new HttpRequest(),
             200,
             headers,
@@ -74,7 +73,7 @@ class HttpResponseSpec extends Specification {
     def 'When the response contains no entity, hasEntity() returns false'() {
         setup:
         HttpResponse response = new MockHttpResponse(
-            new EntityConverterManager(),
+            new EntityConverterManager([]),
             new HttpRequest(),
             200,
             new MultiValuedMap(),
@@ -90,7 +89,7 @@ class HttpResponseSpec extends Specification {
         HttpRequest request = new HttpRequest().setBufferResponseEntity(false)
         HttpEntity entity = new HttpEntity(new ByteArrayInputStream([1, 2, 3] as byte[]))
         HttpResponse response = new MockHttpResponse(
-            new EntityConverterManager(),
+            new EntityConverterManager([]),
             request,
             200,
             new MultiValuedMap(),

http-requests-core/src/test/groovy/com/budjb/httprequests/converter/EntityConverterManagerSpec.groovy

@@ -24,12 +24,9 @@ class EntityConverterManagerSpec extends Specification {
     def 'When an EntityConverter is added, the manager contains it'() {
         setup:
         EntityConverter converter = Mock(EntityConverter)
-        EntityConverterManager manager = new EntityConverterManager()
+        EntityConverterManager manager = new EntityConverterManager([converter])
 
-        when:
-        manager.add(converter)
-
-        then:
+        expect:
         manager.getAll().size() == 1
         manager.getAll().get(0).is converter
     }
@@ -39,54 +36,18 @@ class EntityConverterManagerSpec extends Specification {
         EntityConverter c1 = Mock(EntityConverter)
         EntityConverter c2 = Mock(EntityConverter)
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(c1)
-        manager.add(c2)
+        EntityConverterManager manager = new EntityConverterManager([c1, c2])
 
         expect:
         manager.getAll() == [c1, c2]
     }
 
-    def 'After removing a converter, it is no longer contained in the manager'() {
-        setup:
-        EntityConverter converter = Mock(EntityConverter)
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(converter)
-
-        expect:
-        manager.getAll().contains(converter)
-
-        when:
-        manager.remove(converter)
-
-        then:
-        !manager.getAll().contains(converter)
-    }
-
-    def 'After clearing the manager, no converters are contained in the manager'() {
-        setup:
-        EntityConverter ec1 = Mock(EntityConverter)
-        EntityConverter ec2 = Mock(EntityConverter)
-
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(ec1)
-        manager.add(ec2)
-
-        when:
-        manager.clear()
-
-        then:
-        manager.getAll().size() == 0
-    }
-
     def 'When getting entity readers, only entity converters that are readers are returned'() {
         setup:
         EntityWriter ec1 = Mock(EntityWriter)
         EntityReader ec2 = Mock(EntityReader)
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(ec1)
-        manager.add(ec2)
+        EntityConverterManager manager = new EntityConverterManager([ec1, ec2])
 
         when:
         List<EntityReader> readers = manager.getEntityReaders()
@@ -101,9 +62,7 @@ class EntityConverterManagerSpec extends Specification {
         EntityWriter ec1 = Mock(EntityWriter)
         EntityReader ec2 = Mock(EntityReader)
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(ec1)
-        manager.add(ec2)
+        EntityConverterManager manager = new EntityConverterManager([ec1, ec2])
 
         when:
         List<EntityWriter> writers = manager.getEntityWriters()
@@ -119,10 +78,7 @@ class EntityConverterManagerSpec extends Specification {
         EntityReader bad = Mock(EntityReader)
         EntityWriter writer = Mock(EntityWriter)
 
-        EntityConverterManager converterManager = new EntityConverterManager()
-        converterManager.add(bad)
-        converterManager.add(good)
-        converterManager.add(writer)
+        EntityConverterManager converterManager = new EntityConverterManager([bad, good, writer])
 
         good.supports(String) >> true
 
@@ -144,10 +100,7 @@ class EntityConverterManagerSpec extends Specification {
         EntityWriter bad = Mock(EntityWriter)
         EntityReader reader = Mock(EntityReader)
 
-        EntityConverterManager converterManager = new EntityConverterManager()
-        converterManager.add(bad)
-        converterManager.add(good)
-        converterManager.add(reader)
+        EntityConverterManager converterManager = new EntityConverterManager([bad, good, reader])
 
         good.supports(String) >> true
 
@@ -165,7 +118,7 @@ class EntityConverterManagerSpec extends Specification {
 
     def 'When no reader is available to perform conversion, an UnsupportedConversionException is thrown'() {
         setup:
-        EntityConverterManager converterManager = new EntityConverterManager()
+        EntityConverterManager converterManager = new EntityConverterManager([])
 
         HttpEntity entity = new HttpEntity(new ByteArrayInputStream([1, 2, 3] as byte[]), null, null)
 
@@ -178,7 +131,7 @@ class EntityConverterManagerSpec extends Specification {
 
     def 'When no writer is available to perform conversion, an UnsupportedConversionException is thrown'() {
         setup:
-        EntityConverterManager converterManager = new EntityConverterManager()
+        EntityConverterManager converterManager = new EntityConverterManager([])
 
         when:
         converterManager.write('Hello!', null, null)
@@ -192,8 +145,7 @@ class EntityConverterManagerSpec extends Specification {
         EntityWriter converter = Mock(EntityWriter)
         converter.supports(_) >> true
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(converter)
+        EntityConverterManager manager = new EntityConverterManager([converter])
 
         when:
         manager.write('foo')
@@ -213,9 +165,7 @@ class EntityConverterManagerSpec extends Specification {
         c2.supports(_) >> true
         c2.write(*_) >> inputStream
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(c1)
-        manager.add(c2)
+        EntityConverterManager manager = new EntityConverterManager([c1, c2])
 
         when:
         HttpEntity entity = manager.write('foo')
@@ -236,9 +186,7 @@ class EntityConverterManagerSpec extends Specification {
         c2.supports(_) >> true
         c2.write(*_) >> inputStream
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(c1)
-        manager.add(c2)
+        EntityConverterManager manager = new EntityConverterManager([c1, c2])
 
         when:
         HttpEntity entity = manager.write('foo')
@@ -257,9 +205,7 @@ class EntityConverterManagerSpec extends Specification {
         c2.supports(_) >> true
         c2.read(*_) >> 'foo'
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(c1)
-        manager.add(c2)
+        EntityConverterManager manager = new EntityConverterManager([c1, c2])
 
         HttpEntity entity = Mock(HttpEntity)
         entity.getInputStream() >> Mock(InputStream)
@@ -277,8 +223,7 @@ class EntityConverterManagerSpec extends Specification {
         c1.supports(_) >> true
         c1.read(*_) >> { throw new IOException() }
 
-        EntityConverterManager manager = new EntityConverterManager()
-        manager.add(c1)
+        EntityConverterManager manager = new EntityConverterManager([c1])
 
         HttpEntity entity = Mock(HttpEntity)
         entity.getInputStream() >> Mock(InputStream)