Remove verbose Java global lock implementation

internal/zinc-ivy-integration/src/main/java/sbt/inc/ZincBridgeProvider.java

@@ -47,20 +47,6 @@ public final class ZincBridgeProvider {
         return ZincComponentCompiler$.MODULE$.getDefaultConfiguration(baseDirectory, ivyHome, resolvers, logger);
     }
 
-    /**
-     * Cast a CheckedException as an unchecked one.
-     *
-     * @param throwable to cast
-     * @param <T>       the type of the Throwable
-     * @return this method will never return a Throwable instance, it will just throw it.
-     * @throws T the throwable as an unchecked throwable
-     */
-    @SuppressWarnings("unchecked")
-    private static <T extends Throwable> RuntimeException rethrow(Throwable throwable) throws T {
-        throw (T) throwable; // rely on vacuous cast
-    }
-
-
     /**
      * Defines a global lock that does nothing but calling the callable to synchronize
      * across threads. The lock file is used to resolve and download dependencies via ivy.
@@ -70,19 +56,7 @@ public final class ZincBridgeProvider {
      * @return A default global lock.
      */
     public static GlobalLock getDefaultLock() {
-        return new GlobalLock() {
-            @Override
-            public <T> T apply(File lockFile, Callable<T> run) {
-                T value = null;
-                try {
-                    value = run.call();
-                } catch (Exception e) {
-                    // Rethrow runtime exception because apply does not define throwing Exception
-                    rethrow(e);
-                }
-                return value;
-            }
-        };
+        return ZincComponentCompiler$.MODULE$.getDefaultLock();
     }
 
     /**

internal/zinc-ivy-integration/src/main/scala/sbt/internal/inc/ZincComponentCompiler.scala

@@ -11,6 +11,7 @@ package inc
 
 import java.io.File
 import java.net.URLClassLoader
+import java.util.concurrent.Callable
 
 import sbt.internal.inc.classpath.ClasspathUtilities
 import sbt.io.{ Hash, IO }
@@ -19,6 +20,7 @@ import sbt.internal.util.FullLogger
 import sbt.librarymanagement._
 import sbt.librarymanagement.syntax._
 import sbt.util.{ InterfaceUtil, Logger }
+import xsbti.GlobalLock
 import xsbti.compile.CompilerBridgeProvider
 
 private[sbt] object ZincComponentCompiler {
@@ -145,6 +147,10 @@ private[sbt] object ZincComponentCompiler {
     FileRepository("local", Resolver.defaultFileConfiguration, finalPatterns)
   }
 
+  def getDefaultLock: GlobalLock = new GlobalLock {
+    override def apply[T](file: File, callable: Callable[T]): T = callable.call()
+  }
+
   def getDefaultConfiguration(baseDirectory: File,
                               ivyHome: File,
                               resolvers0: Array[Resolver],