@PreAuthorize("principal.somePrincipalMethod(#request.property1, #request.property2, 'stringA', 'stringB')")
public SomeResponse someWebServiceMethod1(SomeRequest request) {
    ...
}
@PreAuthorize("principal.somePrincipalMethod(#request.property1, 'stringA', 'stringB', 'stringC')")
public SomeResponse someWebServiceMethod2(SomeRequest request) {
    ...
}
public class SomeRequest {
    Long property1;
    Long property2;
}

public boolean somePrincipalMethod(Long longParam1, Long longParam2, String... stringParams) {
    return true;
}
public boolean somePrincipalMethod(Long longParam, String... stringParams) {
    return true;
}

someWebServiceMethod1(new SomeRequest(1L, 2L))

somePrincipalMethod(1L, {"2", "stringA", "stringB"})

somePrincipalMethod(1L, 2L, {"stringA", "stringB"})

@PreAuthorize("principal.somePrincipalMethod(#request.property1, #request.property2, {'stringA', 'stringB'})")
public SomeResponse someWebServiceMethod1(SomeRequest request) {
    ...
}
@PreAuthorize("principal.somePrincipalMethod(#request.property1, {'stringA', 'stringB', 'stringC'})")
public SomeResponse someWebServiceMethod2(SomeRequest request) {
    ...
}

public boolean somePrincipalMethod(Long longParam1, Long longParam2, String[] stringParams) {
    return true;
}
public boolean somePrincipalMethod(Long longParam, String[] stringParams) {
    return true;
}