Is there any Java API for that? How can I read this information.
To have frequency on Android, just read these special files in /sys directory:
#cat "/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq"
#cat "/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq"
#cat "/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq"
You will have current, min and max Frequency allowed.