Memory leak to measure coverage

[mzw]

When running cov command at commons-math, I faced on the following error that might indicate memory leak. I reran the command with After option and completed to measure coverage, but it was not useful to users. Debugging this memory leak can increase the usefulness of VTR.

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
        at java.util.Arrays.copyOf(Arrays.java:3236)
        at java.lang.StringCoding.safeTrim(StringCoding.java:79)
        at java.lang.StringCoding.access$300(StringCoding.java:50)
        at java.lang.StringCoding$StringEncoder.encode(StringCoding.java:305)
        at java.lang.StringCoding.encode(StringCoding.java:344)
        at java.lang.StringCoding.encode(StringCoding.java:387)
        at java.lang.String.getBytes(String.java:958)
        at jp.mzw.vtr.git.GitUtils.getPatch(GitUtils.java:140)
        at jp.mzw.vtr.detect.Detector.getTestCaseModifications(Detector.java:244)
        at jp.mzw.vtr.detect.Detector.onCheckout(Detector.java:86)
        at jp.mzw.vtr.git.CheckoutConductor.onCheckout(CheckoutConductor.java:52)
        at jp.mzw.vtr.git.CheckoutConductor.checkout(CheckoutConductor.java:133)
        at jp.mzw.vtr.git.CheckoutConductor.checkout(CheckoutConductor.java:78)
        at jp.mzw.vtr.command.DetectCommand.detect(DetectCommand.java:35)
        at jp.mzw.vtr.command.DetectCommand.command(DetectCommand.java:21)
        at jp.mzw.vtr.CLI.main(CLI.java:37)