package com.easternedgerobotics.rov.io;

import com.easternedgerobotics.rov.value.CpuValue;

import com.pi4j.system.SystemInfo;
import rx.Observable;
import rx.exceptions.Exceptions;
import rx.schedulers.Schedulers;

import java.io.IOException;
import java.util.concurrent.TimeUnit;

public final class CpuInformation {
    private final Observable<Long> interval;

    /**
     * Constructs a CpuInformation instance that polls CPU properties at the specified interval.
     *
     * @param interval the interval at which to poll the CPU properties.
     * @param timeUnit the {@code TimeUnit} the interval is specified in.
     */
    public CpuInformation(final int interval, final TimeUnit timeUnit) {
        this.interval = Observable.interval(interval, timeUnit);
    }

    /**
     * Returns an observable stream of CPU values.
     *
     * @return a stream of CPU values.
     */
    public final Observable<CpuValue> observe() {
        return interval.observeOn(Schedulers.io()).map(this::pollCpu);
    }

    private CpuValue pollCpu(final long tick) {
        try {
            return CpuValue.create(
                SystemInfo.getClockFrequencyArm(), SystemInfo.getCpuTemperature(), SystemInfo.getCpuVoltage());
        } catch (final InterruptedException | IOException e) {
            throw Exceptions.propagate(e);
        }
    }
}

package com.easternedgerobotics.rov.io;

import com.easternedgerobotics.rov.value.CpuValue;

import com.pi4j.system.SystemInfo;
import rx.Observable;
import rx.exceptions.Exceptions;
import rx.schedulers.Schedulers;

import java.io.IOException;
import java.util.concurrent.TimeUnit;

public final class CpuInformation {
    private final Observable<Long> interval;

    /**
     * Constructs a CpuInformation instance that polls CPU properties at the specified interval.
     *
     * @param interval the interval at which to poll the CPU properties.
     * @param timeUnit the {@code TimeUnit} the interval is specified in.
     */
    public CpuInformation(final long interval, final TimeUnit timeUnit) {
        this.interval = Observable.interval(interval, timeUnit);
    }

    /**
     * Returns an observable stream of CPU values.
     *
     * @return a stream of CPU values.
     */
    public final Observable<CpuValue> observe() {
        return interval.observeOn(Schedulers.io()).map(this::pollCpu);
    }

    private CpuValue pollCpu(final long tick) {
        try {
            return CpuValue.create(
                SystemInfo.getClockFrequencyArm(), SystemInfo.getCpuTemperature(), SystemInfo.getCpuVoltage());
        } catch (final InterruptedException | IOException e) {
            throw Exceptions.propagate(e);
        }
    }
}

Change CpuInformation ctor signature to accept long interval