oshi.software.common.AbstractOperatingSystem Maven / Gradle / Ivy
/*
* Copyright 2016-2022 The OSHI Project Contributors
* SPDX-License-Identifier: MIT
*/
package oshi.software.common;
import static oshi.software.os.OperatingSystem.ProcessFiltering.ALL_PROCESSES;
import static oshi.software.os.OperatingSystem.ProcessSorting.NO_SORTING;
import static oshi.util.Memoizer.memoize;
import java.util.ArrayDeque;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Queue;
import java.util.Set;
import java.util.function.Predicate;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import com.sun.jna.Platform;
import oshi.software.os.OSProcess;
import oshi.software.os.OperatingSystem;
import oshi.util.GlobalConfig;
import oshi.util.tuples.Pair;
/**
* Common methods for OperatingSystem implementations
*/
public abstract class AbstractOperatingSystem implements OperatingSystem {
protected static final boolean USE_WHO_COMMAND = GlobalConfig.get(GlobalConfig.OSHI_OS_UNIX_WHOCOMMAND, false);
private final Supplier manufacturer = memoize(this::queryManufacturer);
private final Supplier> familyVersionInfo = memoize(this::queryFamilyVersionInfo);
private final Supplier bitness = memoize(this::queryPlatformBitness);
@Override
public String getManufacturer() {
return manufacturer.get();
}
protected abstract String queryManufacturer();
@Override
public String getFamily() {
return familyVersionInfo.get().getA();
}
@Override
public OSVersionInfo getVersionInfo() {
return familyVersionInfo.get().getB();
}
protected abstract Pair queryFamilyVersionInfo();
@Override
public int getBitness() {
return bitness.get();
}
private int queryPlatformBitness() {
if (Platform.is64Bit()) {
return 64;
}
// Initialize based on JVM Bitness. Individual OS implementations will test
// if 32-bit JVM running on 64-bit OS
int jvmBitness = System.getProperty("os.arch").contains("64") ? 64 : 32;
return queryBitness(jvmBitness);
}
/**
* Backup OS-specific query to determine bitness if previous checks fail
*
* @param jvmBitness The bitness of the JVM
* @return The operating system bitness
*/
protected abstract int queryBitness(int jvmBitness);
@Override
public List getProcesses(Predicate filter, Comparator sort, int limit) {
return queryAllProcesses().stream().filter(filter == null ? ALL_PROCESSES : filter)
.sorted(sort == null ? NO_SORTING : sort).limit(limit > 0 ? limit : Long.MAX_VALUE)
.collect(Collectors.toList());
}
protected abstract List queryAllProcesses();
@Override
public List getChildProcesses(int parentPid, Predicate filter, Comparator sort,
int limit) {
// Get this pid and its children
List childProcs = queryChildProcesses(parentPid);
// Extract the parent from the list
OSProcess parent = childProcs.stream().filter(p -> p.getProcessID() == parentPid).findAny().orElse(null);
// Get the parent's start time
long parentStartTime = parent == null ? 0 : parent.getStartTime();
// Get children after parent
return queryChildProcesses(parentPid).stream().filter(filter == null ? ALL_PROCESSES : filter)
.filter(p -> p.getProcessID() != parentPid && p.getStartTime() >= parentStartTime)
.sorted(sort == null ? NO_SORTING : sort).limit(limit > 0 ? limit : Long.MAX_VALUE)
.collect(Collectors.toList());
}
protected abstract List queryChildProcesses(int parentPid);
@Override
public List getDescendantProcesses(int parentPid, Predicate filter,
Comparator sort, int limit) {
// Get this pid and its descendants
List descendantProcs = queryDescendantProcesses(parentPid);
// Extract the parent from the list
OSProcess parent = descendantProcs.stream().filter(p -> p.getProcessID() == parentPid).findAny().orElse(null);
// Get the parent's start time
long parentStartTime = parent == null ? 0 : parent.getStartTime();
// Get descendants after parent
return queryDescendantProcesses(parentPid).stream().filter(filter == null ? ALL_PROCESSES : filter)
.filter(p -> p.getProcessID() != parentPid && p.getStartTime() >= parentStartTime)
.sorted(sort == null ? NO_SORTING : sort).limit(limit > 0 ? limit : Long.MAX_VALUE)
.collect(Collectors.toList());
}
protected abstract List queryDescendantProcesses(int parentPid);
/**
* Utility method for subclasses to take a full process list as input and return the children or descendants of a
* particular process. The process itself is also returned to more efficiently extract its start time for filtering
*
* @param allProcs A collection of all processes
* @param parentPid The process ID whose children or descendants to return
* @param allDescendants If false, only gets immediate children of this process. If true, gets all descendants.
* @return Set of children or descendants of parentPid
*/
protected static Set getChildrenOrDescendants(Collection allProcs, int parentPid,
boolean allDescendants) {
Map parentPidMap = allProcs.stream()
.collect(Collectors.toMap(OSProcess::getProcessID, OSProcess::getParentProcessID));
return getChildrenOrDescendants(parentPidMap, parentPid, allDescendants);
}
/**
* Utility method for subclasses to take a map of pid to parent as input and return the children or descendants of a
* particular process.
*
* @param parentPidMap a map of all processes with processID as key and parentProcessID as value
* @param parentPid The process ID whose children or descendants to return
* @param allDescendants If false, only gets immediate children of this process. If true, gets all descendants.
* @return Set of children or descendants of parentPid, including the parent
*/
protected static Set getChildrenOrDescendants(Map parentPidMap, int parentPid,
boolean allDescendants) {
// Set to hold results
Set descendantPids = new HashSet<>();
descendantPids.add(parentPid);
// Queue for BFS algorithm
Queue queue = new ArrayDeque<>();
queue.add(parentPid);
// Add children, repeating if recursive
do {
for (int pid : getChildren(parentPidMap, queue.poll())) {
if (!descendantPids.contains(pid)) {
descendantPids.add(pid);
queue.add(pid);
}
}
} while (allDescendants && !queue.isEmpty());
return descendantPids;
}
private static Set getChildren(Map parentPidMap, int parentPid) {
return parentPidMap.entrySet().stream()
.filter(e -> e.getValue().equals(parentPid) && !e.getKey().equals(parentPid)).map(Entry::getKey)
.collect(Collectors.toSet());
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(getManufacturer()).append(' ').append(getFamily()).append(' ').append(getVersionInfo());
return sb.toString();
}
}