diff --git a/library/build.gradle b/library/build.gradle
index abb8c49..51d1a34 100644
--- a/library/build.gradle
+++ b/library/build.gradle
@@ -23,6 +23,11 @@
         minSdkVersion 4
     }
 
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_7
+        targetCompatibility JavaVersion.VERSION_1_7
+    }
+
     sourceSets {
         main {
             java.srcDirs         = ['src']