Java 8: computeIfAbsent/withInitial

src/main/org/apache/tools/ant/ComponentHelper.java

@@ -683,11 +683,7 @@ public class ComponentHelper  {
         String name = def.getName();
         List<AntTypeDefinition> list = null;
         synchronized (restrictedDefinitions) {
-            list = restrictedDefinitions.get(name);
-            if (list == null) {
-                list = new ArrayList<>();
-                restrictedDefinitions.put(name, list);
-            }
+            list = restrictedDefinitions.computeIfAbsent(name, k -> new ArrayList<>());
         }
         // Check if the classname is already present and remove it
         // if it is

src/main/org/apache/tools/ant/IntrospectionHelper.java

@@ -1028,8 +1028,7 @@ public final class IntrospectionHelper {
                                                   final String attrName) {
         // use wrappers for primitive classes, e.g. int and
         // Integer are treated identically
-        final Class<?> reflectedArg = PRIMITIVE_TYPE_MAP.containsKey(arg)
-            ? PRIMITIVE_TYPE_MAP.get(arg) : arg;
+        final Class<?> reflectedArg = PRIMITIVE_TYPE_MAP.getOrDefault(arg, arg);
 
         // Object.class - it gets handled differently by AttributeSetter
         if (java.lang.Object.class == reflectedArg) {

src/main/org/apache/tools/ant/Main.java

@@ -406,11 +406,7 @@ public class Main implements AntMain {
                 for (final ArgumentProcessor processor : processorRegistry.getProcessors()) {
                     final int newI = processor.readArguments(args, i);
                     if (newI != -1) {
-                        List<String> extraArgs = extraArguments.get(processor.getClass());
-                        if (extraArgs == null) {
-                            extraArgs = new ArrayList<>();
-                            extraArguments.put(processor.getClass(), extraArgs);
-                        }
+                        List<String> extraArgs = extraArguments.computeIfAbsent(processor.getClass(), k -> new ArrayList<>());
                         for (; i < newI && i < args.length; i++) {
                             extraArgs.add(args[i]);
                         }

src/main/org/apache/tools/ant/Project.java

@@ -179,12 +179,7 @@ public class Project implements ResourceFactory {
 
     /** for each thread, record whether it is currently executing
         messageLogged */
-    private final ThreadLocal<Boolean> isLoggingMessage = new ThreadLocal<Boolean>() {
-            @Override
-            protected Boolean initialValue() {
-                return Boolean.FALSE;
-            }
-        };
+    private final ThreadLocal<Boolean> isLoggingMessage = ThreadLocal.withInitial(() -> Boolean.FALSE);
 
     /**
      * The Ant core classloader--may be <code>null</code> if using

src/main/org/apache/tools/ant/ProjectHelper.java

@@ -202,11 +202,7 @@ public class ProjectHelper {
         targetPrefix.set(prefix);
     }
 
-    private static final ThreadLocal<String> prefixSeparator = new ThreadLocal<String>() {
-            protected String initialValue() {
-                return ".";
-            }
-        };
+    private static final ThreadLocal<String> prefixSeparator = ThreadLocal.withInitial(() -> ".");
 
     /**
      * The separator between the prefix and the target name.
@@ -230,11 +226,7 @@ public class ProjectHelper {
         prefixSeparator.set(sep);
     }
 
-    private static final ThreadLocal<Boolean> inIncludeMode = new ThreadLocal<Boolean>() {
-            protected Boolean initialValue() {
-                return Boolean.FALSE;
-            }
-        };
+    private static final ThreadLocal<Boolean> inIncludeMode = ThreadLocal.withInitial(() -> Boolean.FALSE);
 
     /**
      * Whether the current file should be read in include as opposed

src/main/org/apache/tools/ant/XmlLogger.java

@@ -207,11 +207,7 @@ public class XmlLogger implements BuildLogger {
      * @return the stack of timed elements for the current thread
      */
     private Stack<TimedElement> getStack() {
-        Stack<TimedElement> threadStack = threadStacks.get(Thread.currentThread());
-        if (threadStack == null) {
-            threadStack = new Stack<>();
-            threadStacks.put(Thread.currentThread(), threadStack);
-        }
+        Stack<TimedElement> threadStack = threadStacks.computeIfAbsent(Thread.currentThread(), k -> new Stack<>());
         /* For debugging purposes uncomment:
         org.w3c.dom.Comment s = doc.createComment("stack=" + threadStack);
         buildElement.element.appendChild(s);

src/main/org/apache/tools/ant/helper/AntXMLContext.java

@@ -362,11 +362,7 @@ public class AntXMLContext {
      * @param uri    a namespace uri
      */
     public void startPrefixMapping(String prefix, String uri) {
-        List<String> list = prefixMapping.get(prefix);
-        if (list == null) {
-            list = new ArrayList<>();
-            prefixMapping.put(prefix, list);
-        }
+        List<String> list = prefixMapping.computeIfAbsent(prefix, k -> new ArrayList<>());
         list.add(uri);
     }
 

src/main/org/apache/tools/ant/taskdefs/Copy.java

@@ -1015,11 +1015,7 @@ public class Copy extends Task {
     private static void add(File baseDir, final String[] names, final Map<File, List<String>> m) {
         if (names != null) {
             baseDir = getKeyFile(baseDir);
-            List<String> l = m.get(baseDir);
-            if (l == null) {
-                l = new ArrayList<>(names.length);
-                m.put(baseDir, l);
-            }
+            List<String> l = m.computeIfAbsent(baseDir, k -> new ArrayList<>(names.length));
             l.addAll(Arrays.asList(names));
         }
     }

src/main/org/apache/tools/ant/taskdefs/Definer.java

@@ -54,12 +54,7 @@ public abstract class Definer extends DefBase {
      */
     private static final String ANTLIB_XML = "/antlib.xml";
 
-    private static final ThreadLocal<Map<URL, Location>> RESOURCE_STACK = new ThreadLocal<Map<URL, Location>>() {
-        @Override
-        protected Map<URL, Location> initialValue() {
-            return new HashMap<>();
-        }
-    };
+    private static final ThreadLocal<Map<URL, Location>> RESOURCE_STACK = ThreadLocal.withInitial(HashMap::new);
 
     private String name;
     private String classname;

src/main/org/apache/tools/ant/taskdefs/Javac.java

@@ -1695,11 +1695,7 @@ public class Javac extends MatchingTask {
             final File moduleSourceRoot = pathInModule == null ?
                     module :
                     new File(module, pathInModule);
-            Collection<File> moduleRoots = collector.get(moduleName);
-            if (moduleRoots == null) {
-                moduleRoots = new ArrayList<>();
-                collector.put(moduleName, moduleRoots);
-            }
+            Collection<File> moduleRoots = collector.computeIfAbsent(moduleName, k -> new ArrayList<>());
             moduleRoots.add(moduleSourceRoot);
         }
     }

src/main/org/apache/tools/ant/taskdefs/Tar.java

@@ -605,11 +605,7 @@ public class Tar extends MatchingTask {
                     base = Copy.NULL_FILE_PLACEHOLDER;
                 }
                 basedirs.add(base);
-                List<String> files = basedirToFilesMap.get(base);
-                if (files == null) {
-                    files = new Vector<>();
-                    basedirToFilesMap.put(base, files);
-                }
+                List<String> files = basedirToFilesMap.computeIfAbsent(base, k -> new Vector<>());
                 if (base == Copy.NULL_FILE_PLACEHOLDER) {
                     files.add(r.getFile().getAbsolutePath());
                 } else {

src/main/org/apache/tools/ant/taskdefs/Zip.java

@@ -1296,12 +1296,7 @@ public class Zip extends MatchingTask {
      * to move the withEmpty behavior checks (since either would break
      * subclasses in several ways).
      */
-    private static final ThreadLocal<Boolean> HAVE_NON_FILE_SET_RESOURCES_TO_ADD = new ThreadLocal<Boolean>() {
-            @Override
-            protected Boolean initialValue() {
-                return Boolean.FALSE;
-            }
-        };
+    private static final ThreadLocal<Boolean> HAVE_NON_FILE_SET_RESOURCES_TO_ADD = ThreadLocal.withInitial(() -> Boolean.FALSE);
 
     /**
      * Collect the resources that are newer than the corresponding

src/main/org/apache/tools/ant/taskdefs/cvslib/ChangeLogParser.java

@@ -263,9 +263,8 @@ class ChangeLogParser {
      * Utility method that saves the current entry.
      */
     private void saveEntry() {
-        entries.computeIfAbsent(date + author + comment, k -> {
-            return new CVSEntry(parseDate(date), author, comment);
-        }).addFile(file, revision, previousRevision);
+        entries.computeIfAbsent(date + author + comment,
+                k -> new CVSEntry(parseDate(date), author, comment)).addFile(file, revision, previousRevision);
     }
 
     /**

src/main/org/apache/tools/ant/taskdefs/optional/i18n/Translate.java

@@ -458,9 +458,7 @@ public class Translate extends MatchingTask {
                         }
                         if (key.length() > 0) {
                             //Has key already been loaded into resourceMap?
-                            if (resourceMap.get(key) == null) {
-                                resourceMap.put(key, value);
-                            }
+                            resourceMap.putIfAbsent(key, value);
                         }
                     }
                 }

src/main/org/apache/tools/ant/util/DateUtils.java

@@ -98,12 +98,7 @@ public final class DateUtils {
      * @since Ant 1.10.2
      */
     public static final ThreadLocal<DateFormat> EN_US_DATE_FORMAT_MIN =
-        new ThreadLocal<DateFormat>() {
-            @Override
-            protected DateFormat initialValue() {
-                return new SimpleDateFormat("MM/dd/yyyy hh:mm a", Locale.US);
-            }
-        };
+            ThreadLocal.withInitial(() -> new SimpleDateFormat("MM/dd/yyyy hh:mm a", Locale.US));
 
     /**
      * Provides a thread-local US-style date format. Exactly as used by
@@ -112,12 +107,7 @@ public final class DateUtils {
      * @since Ant 1.10.2
      */
     public static final ThreadLocal<DateFormat> EN_US_DATE_FORMAT_SEC =
-        new ThreadLocal<DateFormat>() {
-            @Override
-            protected DateFormat initialValue() {
-                return new SimpleDateFormat("MM/dd/yyyy hh:mm:ss a", Locale.US);
-            }
-        };
+            ThreadLocal.withInitial(() -> new SimpleDateFormat("MM/dd/yyyy hh:mm:ss a", Locale.US));
 
     static {
         MINUTE_SECONDS.setFormat(0, MINUTES_FORMAT);
@@ -329,12 +319,10 @@ public final class DateUtils {
     }
 
     final private static ThreadLocal<DateFormat> iso8601WithTimeZone =
-        new ThreadLocal<DateFormat>() {
-            @Override protected DateFormat initialValue() {
+            ThreadLocal.withInitial(() -> {
               // An arbitrary easy-to-read format to normalize to.
               return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS Z");
-            }
-        };
+            });
     final private static Pattern iso8601normalizer = Pattern.compile(
         "^(\\d{4,}-\\d{2}-\\d{2})[Tt ]" +           // yyyy-MM-dd
         "(\\d{2}:\\d{2}(:\\d{2}(\\.\\d{3})?)?) ?" + // HH:mm:ss.SSS

src/main/org/apache/tools/zip/ZipFile.java

@@ -889,11 +889,7 @@ public class ZipFile implements Closeable {
             }
 
             final String name = ze.getName();
-            LinkedList<ZipEntry> entriesOfThatName = nameMap.get(name);
-            if (entriesOfThatName == null) {
-                entriesOfThatName = new LinkedList<>();
-                nameMap.put(name, entriesOfThatName);
-            }
+            LinkedList<ZipEntry> entriesOfThatName = nameMap.computeIfAbsent(name, k -> new LinkedList<>());
             entriesOfThatName.addLast(ze);
         }
     }