diff --git a/build.gradle b/build.gradle
index 3678076f..3a6ae755 100644
--- a/build.gradle
+++ b/build.gradle
@@ -185,7 +185,7 @@ buildscript {
     }
 }
 
-task wrapper(type: Wrapper) {
-    gradleVersion = '4.6'
+wrapper {
+    gradleVersion = '5.1'
     distributionType = Wrapper.DistributionType.ALL
 }
diff --git a/dexlib2/build.gradle b/dexlib2/build.gradle
index b8fe7894..b6a7490c 100644
--- a/dexlib2/build.gradle
+++ b/dexlib2/build.gradle
@@ -81,7 +81,7 @@ task generateAccessorTestDex(type: JavaExec, dependsOn: compileAccessorTestJava)
     def outputDex = file('src/test/resources/accessorTest.dex')
     file(outputDex.parent).mkdirs()
 
-    inputs.dir(project.sourceSets.accessorTest.output.classesDir)
+    inputs.dir(project.sourceSets.accessorTest.output.classesDirs)
     outputs.file outputDex
 
     main 'com.android.dx.command.Main'
@@ -90,7 +90,7 @@ task generateAccessorTestDex(type: JavaExec, dependsOn: compileAccessorTestJava)
     args '--dex'
     args '--no-strict'
     args "--output=${outputDex}"
-    args sourceSets.accessorTest.output.classesDir
+    args sourceSets.accessorTest.output.classesDirs
 }
 
 uploadArchives {
@@ -102,4 +102,4 @@ uploadArchives {
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
index f6b961fd..87b738cb 100644
Binary files a/gradle/wrapper/gradle-wrapper.jar and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 9a4163a4..10cb99e6 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.1-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
index cccdd3d5..af6708ff 100755
--- a/gradlew
+++ b/gradlew
@@ -28,7 +28,7 @@ APP_NAME="Gradle"
 APP_BASE_NAME=`basename "$0"`
 
 # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS=""
+DEFAULT_JVM_OPTS='"-Xmx64m"'
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD="maximum"
diff --git a/gradlew.bat b/gradlew.bat
index e95643d6..0f8d5937 100644
--- a/gradlew.bat
+++ b/gradlew.bat
@@ -14,7 +14,7 @@ set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
 @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-set DEFAULT_JVM_OPTS=
+set DEFAULT_JVM_OPTS="-Xmx64m"
 
 @rem Find java.exe
 if defined JAVA_HOME goto findJavaFromJavaHome