Java 1.7 compatibility problem

Hi, I wanted to add your project into my android stodio project using gradle but I faced this error

Error:Error converting bytecode to dex: Cause: Dex cannot parse version 52 byte code. This is caused by library dependencies that have been compiled using Java 8 or above. If you are using the 'java' gradle plugin in a library submodule add targetCompatibility = '1.7' sourceCompatibility = '1.7' to that submodule's build.gradle file.

Is there any solutions to fix it?

[lemmingapex]

@junaidyasin Glad you were able to get jack options working for your build. Do you have any advice for @am2222?

Internally, the trilateration library uses the Apache Commons Mathematics Library. Judging by the error @junaidyasin posted, it looks like some of the apache common math library is being passed through the jack toolchain, and the virtual machine might be running out of memory. The section of apache common math that gets spit out in this error is in the file FastMathLiteralArrays.java, which contains several long arrays of doubles (these appear to be precomputed values that the math library uses). So a memory exception makes sense. If your machine has more available memory, you might see if it’s possible to allocate more memory to this process. I’m not entirely sure how to do this, but the error suggests that adding something to gradle.properties might work. Something like this would give the vm a maximum of 4GB:

org.gradle.jvmargs=-Xmx4096m

Hope that information is helpful. Let me know if find something that works. Thanks.

[lemmingapex]

@am2222 Great, glad you got it working. Feel free to hit me up if you have more questions. If you guys found the library helpful, please consider starring trilateration on github. Thanks!