Changed JsonEncoder to not prefix output with spaces.

Starting from the second object JsonEncoder added a space character to
each serialised object it generated (as pointed out in issue #152). This
commit changes the configuration of the JSON generator used by
JsonEncoder to not output these spaces.

Author: cboehme

src/main/java/org/culturegraph/mf/stream/converter/JsonEncoder.java

@@ -53,7 +53,8 @@ public final class JsonEncoder extends
 	public JsonEncoder() {
 		try {
 			jsonGenerator = new JsonFactory().createGenerator(writer);
-		} catch (IOException e) {
+			jsonGenerator.setRootValueSeparator(null);
+		} catch (final IOException e) {
 			throw new MetafactureException(e);
 		}
 	}
@@ -70,8 +71,8 @@ public void endRecord() {
 		endGroup();
 		try {
 			jsonGenerator.flush();
-		} catch (IOException e) {
-			throw new MetafactureException(e); 
+		} catch (final IOException e) {
+			throw new MetafactureException(e);
 		}
 		getReceiver().process(writer.toString());
 	}
@@ -82,7 +83,7 @@ public void startEntity(final String name) {
 	}
 
 	@Override
-	public void endEntity() {	
+	public void endEntity() {
 		endGroup();
 	}
 
@@ -98,10 +99,10 @@ public void literal(final String name, final String value) {
 			} else {
 				jsonGenerator.writeString(value);
 			}
-		} catch (JsonGenerationException e) {
-			throw new MetafactureException(e); 
+		} catch (final JsonGenerationException e) {
+			throw new MetafactureException(e);
 		}
-		catch (IOException e) {
+		catch (final IOException e) {
 			throw new MetafactureException(e);
 		}
 	}
@@ -113,17 +114,17 @@ private void startGroup(final String name) {
 				if (ctx.inObject()) {
 					jsonGenerator.writeFieldName(name.substring(0, name.length() - ARRAY_MARKER.length()));
 				}
-				jsonGenerator.writeStartArray(); 				
-			} else {		
+				jsonGenerator.writeStartArray();
+			} else {
 				if (ctx.inObject()) {
 					jsonGenerator.writeFieldName(name);
 				}
 				jsonGenerator.writeStartObject();
 			}
-		} catch (JsonGenerationException e) {
-			throw new MetafactureException(e); 
+		} catch (final JsonGenerationException e) {
+			throw new MetafactureException(e);
 		}
-		catch (IOException e) {
+		catch (final IOException e) {
 			throw new MetafactureException(e);
 		}
 	}
@@ -136,10 +137,10 @@ private void endGroup() {
 			} else if (ctx.inArray()) {
 				jsonGenerator.writeEndArray();
 			}
-		} catch (JsonGenerationException e) {
-			throw new MetafactureException(e); 
+		} catch (final JsonGenerationException e) {
+			throw new MetafactureException(e);
 		}
-		catch (IOException e) {
+		catch (final IOException e) {
 			throw new MetafactureException(e);
 		}
 	}

src/test/java/org/culturegraph/mf/stream/converter/JsonEncoderTest.java

@@ -15,12 +15,14 @@
  */
 package org.culturegraph.mf.stream.converter;
 
+import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.verify;
 
 import org.culturegraph.mf.framework.ObjectReceiver;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
+import org.mockito.InOrder;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
@@ -58,7 +60,7 @@ public final class JsonEncoderTest {
 	public void setup() {
 		MockitoAnnotations.initMocks(this);
 		encoder = new JsonEncoder();
-		encoder.setReceiver(receiver); 
+		encoder.setReceiver(receiver);
 	}
 
 	@After
@@ -107,7 +109,7 @@ public void testShouldEncodeNestedEntities() {
 	}
 
 	@Test
-	public void testShouldEncodeMarkedEntitiesAsList() {	
+	public void testShouldEncodeMarkedEntitiesAsList() {
 		encoder.startRecord("");
 		encoder.startEntity(LIST1);
 		encoder.literal(LITERAL1, VALUE1);
@@ -164,6 +166,20 @@ public void testShouldOutputDuplicateNames() {
 
 		verify(receiver).process(fixQuotes("{'L1':'V1','L1':'V2'}"));
 	}
+	
+	@Test
+	public void testIssue152ShouldNotPrefixOutputWithSpaces() {
+		encoder.startRecord("");
+		encoder.literal(LITERAL1, VALUE1);
+		encoder.endRecord();
+		encoder.startRecord("");
+		encoder.literal(LITERAL2, VALUE2);
+		encoder.endRecord();
+
+		final InOrder ordered = inOrder(receiver);
+		ordered.verify(receiver).process(fixQuotes("{'L1':'V1'}"));
+		ordered.verify(receiver).process(fixQuotes("{'L2':'V2'}"));
+	}
 
 	/*
 	 * Utility method which replaces all single quotes in a string with double quotes.