micro-libgcj is available under the same license as libgcj: the GPL with an exception allowing you to link it with independent modules which are not subject to the GPL. See the LIBGCJ_LICENSE and COPYING files included in the source tree for details.
micro-swt is available under the same licenses as the unmodified SWT sources, which vary somewhat by component. The code is primarily covered by the EPL. See the source files for details.