### Question:
GeneralizedParetoDistribution implements ProbabilityDistribution<Double> { @Override public double getCDF(Double x) { ArgChecker.notNull(x, "x"); return 1 - Math.pow(1 + _ksi * getZ(x), -1. / _ksi); } GeneralizedParetoDistribution(double mu, double sigma, double ksi);  GeneralizedParetoDistribution(double mu, double sigma, double ksi, RandomEngine engine); double getMu(); double getSigma(); double getKsi(); @Override double getCDF(Double x); @Override double getInverseCDF(Double p); @Override double getPDF(Double x); @Override double nextRandom(); @Override int hashCode(); @Override boolean equals(Object obj);  }### Answer:
@Test public void testSupport() { ProbabilityDistribution<Double> dist = new GeneralizedParetoDistribution(MU, SIGMA, KSI, ENGINE); assertLimit(dist, MU - EPS); assertThat(dist.getCDF(MU + EPS)).isCloseTo(0, offset(EPS)); assertThat(dist.getCDF(LARGE_X)).isCloseTo(1, offset(EPS)); dist = new GeneralizedParetoDistribution(MU, SIGMA, -KSI); final double limit = MU + SIGMA / KSI; assertLimit(dist, MU - EPS); assertLimit(dist, limit + EPS); assertThat(dist.getCDF(MU + EPS)).isCloseTo(0, offset(EPS)); assertThat(dist.getCDF(limit - 1e-15)).isCloseTo(1, offset(EPS)); }