Change the way to install maven

appveyor.yml

@@ -2,9 +2,17 @@ environment:
     matrix:
         - JAVA_HOME: C:\Program Files\Java\jdk1.8.0
 install:
-  - ps: choco install maven
-  - cmd: SET PATH=C:\tools\apache-maven-3.3.3\bin;%JAVA_HOME%\bin;%PATH%
-  - mvn --version
+  - ps: |
+      Add-Type -AssemblyName System.IO.Compression.FileSystem
+      if (!(Test-Path -Path "C:\maven" )) {
+        (new-object System.Net.WebClient).DownloadFile('http://www.us.apache.org/dist/maven/maven-3/3.3.9/binaries/apache-maven-3.3.9-bin.zip', 'C:\maven-bin.zip')
+        [System.IO.Compression.ZipFile]::ExtractToDirectory("C:\maven-bin.zip", "C:\maven")
+      }
+  - cmd: SET PATH=C:\maven\apache-maven-3.3.9\bin;%JAVA_HOME%\bin;%PATH%
+  - cmd: SET MAVEN_OPTS=-XX:MaxPermSize=1g -Xmx2g
+  - cmd: SET JAVA_OPTS=-XX:MaxPermSize=1g -Xmx2g
+  - cmd: mvn --version
+  - cmd: java -version
 build_script:
   - mvn package
 artifacts: