[MNG-8350] Improve storage and computation of locations in model objects

[jira-importer]

Guillaume Nodet opened MNG-8350 and commented

The Build constructor has the following code:

Map<Object, InputLocation> newlocs = builder.locations != null ? builder.locations : Collections.emptyMap();
Map<Object, InputLocation> oldlocs = builder.base != null && builder.base.locations != null ? builder.base.locations : Collections.emptyMap();
Map<Object, InputLocation> mutableLocations = new HashMap<>(super.locations);
mutableLocations.put("sourceDirectory", newlocs.containsKey("sourceDirectory") ? newlocs.get("sourceDirectory") : oldlocs.get("sourceDirectory"));
mutableLocations.put("scriptSourceDirectory", newlocs.containsKey("scriptSourceDirectory") ? newlocs.get("scriptSourceDirectory") : oldlocs.get("scriptSourceDirectory"));
mutableLocations.put("testSourceDirectory", newlocs.containsKey("testSourceDirectory") ? newlocs.get("testSourceDirectory") : oldlocs.get("testSourceDirectory"));
mutableLocations.put("outputDirectory", newlocs.containsKey("outputDirectory") ? newlocs.get("outputDirectory") : oldlocs.get("outputDirectory"));
mutableLocations.put("testOutputDirectory", newlocs.containsKey("testOutputDirectory") ? newlocs.get("testOutputDirectory") : oldlocs.get("testOutputDirectory"));
mutableLocations.put("extensions", newlocs.containsKey("extensions") ? newlocs.get("extensions") : oldlocs.get("extensions"));
this.locations = Collections.unmodifiableMap(mutableLocations);

This is inefficient, especially when building models programmatically, in which cases locations are usually not set. The code will always store a null value for each key, whereas an empty map could be sufficient if there's no actual values.

The generator code is located at:

maven/src/mdo/model.vm

Lines 174 to 186 in b370e5e

	Map<Object, InputLocation> newlocs = builder.locations != null ? builder.locations : Collections.emptyMap();
	Map<Object, InputLocation> oldlocs = builder.base != null && builder.base.locations != null ? builder.base.locations : Collections.emptyMap();
	#if ( ! $class.superClass )
	Map<Object, InputLocation> mutableLocations = new HashMap<>();
	this.importedFrom = builder.importedFrom;
	mutableLocations.put("", newlocs.containsKey("") ? newlocs.get("") : oldlocs.get(""));
	#else
	Map<Object, InputLocation> mutableLocations = new HashMap<>(super.locations);
	#end
	#foreach ( $field in $class.getFields($version) )
	mutableLocations.put("${field.name}", newlocs.containsKey("${field.name}") ? newlocs.get("${field.name}") : oldlocs.get("${field.name}"));
	#end
	this.locations = Collections.unmodifiableMap(mutableLocations);

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Affects: 4.0.0-beta-5

Remote Links:

• GitHub Pull Request #1847
  

Backported to: 4.0.0-rc-1