### Question:
SfcNshHeader { public boolean isValid(SfcNshHeader sfcNshHeader) { if (sfcNshHeader.nshTunIpDst == null) return false; if (sfcNshHeader.nshNspToChain == null) return false; if (sfcNshHeader.nshNspFromChain == null) return false; if (sfcNshHeader.nshNsiToChain == null) return false; if (sfcNshHeader.nshNsiFromChain == null) return false; if (sfcNshHeader.nshMetaC1 == null) return false; if (sfcNshHeader.nshMetaC2 == null) return false; return true; } private  SfcNshHeader(SfcNshHeaderBuilder builder); boolean isValid(SfcNshHeader sfcNshHeader); Ipv4Address getNshTunIpDst(); PortNumber getNshTunUdpPort(); Long getNshNspToChain(); Short getNshNsiToChain(); Long getNshNspFromChain(); Short getNshNsiFromChain(); Long getNshMetaC1(); Long getNshMetaC2(); static Long convertIpAddressToLong(Ipv4Address ipv4Address); static int getType();  }### Answer:
@Test public void builderTest() { Assert.assertTrue(header.isValid(header)); builder = new SfcNshHeaderBuilder(header); header = builder.build(); Assert.assertTrue(header.isValid(header)); }