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# 开源算法框架Open Tabu Search怎么编写VRPTW的JAVA代码
## 一、VRPTW问题与禁忌搜索算法概述
### 1.1 VRPTW问题定义
车辆路径问题与时间窗约束(Vehicle Routing Problem with Time Windows, VRPTW)是经典的组合优化问题,其核心是在满足以下约束条件下规划最优配送路线:
- **车辆容量限制**:每辆车的载重不能超过最大容量
- **时间窗约束**:客户点必须在指定的时间窗口内被服务
- **路径完整性**:每辆车从仓库出发并最终返回仓库
- **服务唯一性**:每个客户点只能被一辆车服务一次
数学建模通常包含以下要素:
```math
\min \sum_{k \in K} \sum_{(i,j) \in A} c_{ij}x_{ijk}
s.t.
\sum_{k \in K} \sum_{j \in V} x_{ijk} = 1 \quad \forall i \in C
\sum_{i \in C} q_i \sum_{j \in V} x_{ijk} \leq Q \quad \forall k \in K
a_i \leq s_{ik} \leq b_i \quad \forall i \in V, k \in K
禁忌搜索(Tabu Search)是一种元启发式算法,其核心机制包括: - 禁忌表:记录近期移动以避免循环 - 解的评价函数:通常采用总行驶距离或违反约束的惩罚值 - 邻域结构:常用的有2-opt、relocate、exchange等算子 - 特赦准则:当禁忌移动能获得更优解时破禁
Open Tabu Search是开源的Java实现框架,主要特性包括: - 模块化设计(解表示、邻域操作、禁忌策略可扩展) - 支持多线程并行搜索 - 提供可视化监控接口 - 内置常用VRP算子实现
// 框架主要类关系
classDiagram
class Solution
class Move
class TabuList
class Neighborhood
class ObjectiveFunction
class TabuSearch
TabuSearch --> Solution
TabuSearch --> TabuList
TabuSearch --> Neighborhood
TabuSearch --> ObjectiveFunction
Neighborhood --> Move
创建客户点和车辆模型:
public class Customer {
private int id;
private double x, y; // 坐标
private double demand; // 需求量
private TimeWindow timeWindow; // 时间窗
private double serviceTime; // 服务时长
}
public class Vehicle {
private int capacity;
private Depot depot; // 所属仓库
}
采用贪婪算法构造初始可行解:
public class InitialSolutionBuilder {
public Solution generate(List<Customer> customers, List<Vehicle> vehicles) {
Solution solution = new Solution();
// 按时间窗最早开始时间排序
customers.sort(Comparator.comparing(c -> c.getTimeWindow().start()));
for (Customer c : customers) {
boolean inserted = false;
for (Route route : solution.getRoutes()) {
if (canInsert(route, c)) {
insertAtBestPosition(route, c);
inserted = true;
break;
}
}
if (!inserted && solution.getRoutes().size() < vehicles.size()) {
createNewRouteWithCustomer(c);
}
}
return solution;
}
}
实现三种常用邻域算子:
public class RelocateMove implements Move {
public Solution apply(Solution solution) {
// 选择要移动的客户点
Customer customer = selectCustomerToMove();
// 从原路径移除
Route originRoute = removeFromRoute(customer);
// 尝试插入到其他路径
for (Route targetRoute : solution.getRoutes()) {
if (targetRoute != originRoute) {
for (int pos : getFeasiblePositions(targetRoute, customer)) {
Solution newSolution = solution.copy();
newSolution.insertCustomer(targetRoute, pos, customer);
if (isFeasible(newSolution)) return newSolution;
}
}
}
return solution;
}
}
public class ExchangeMove implements Move {
public Solution apply(Solution solution) {
// 选择两条不同路径上的客户点
Pair<Customer, Customer> exchangePair = selectExchangePair();
// 交换位置并验证可行性
Solution newSolution = solution.copy();
newSolution.exchangeCustomers(exchangePair);
return isFeasible(newSolution) ? newSolution : solution;
}
}
实现基于属性禁忌的策略:
public class VRPTWTabuList implements TabuList {
private Deque<TabuAttribute> tabuQueue;
private int tenure = 7; // 禁忌长度
public boolean isTabu(Move move) {
return tabuQueue.stream()
.anyMatch(attr -> attr.matches(move.getAttributes()));
}
public void addTabu(Move move) {
tabuQueue.addLast(move.getAttributes());
if (tabuQueue.size() > tenure) {
tabuQueue.removeFirst();
}
}
}
考虑距离成本和时间窗违反惩罚:
public class VRPTWObjective implements ObjectiveFunction {
private double distanceWeight = 1.0;
private double timeViolationWeight = 100.0;
public double evaluate(Solution solution) {
double totalCost = 0;
// 计算总行驶距离
for (Route route : solution.getRoutes()) {
totalCost += distanceWeight * calculateRouteDistance(route);
}
// 计算时间窗违反惩罚
totalCost += timeViolationWeight * calculateTimeViolations(solution);
return totalCost;
}
}
public class VRPTWSolver {
public Solution solve(ProblemInstance instance, int maxIterations) {
// 初始化
Solution bestSolution = InitialSolutionBuilder.build(instance);
Solution currentSolution = bestSolution.copy();
TabuList tabuList = new VRPTWTabuList();
// 迭代搜索
for (int iter = 0; iter < maxIterations; iter++) {
// 生成候选解
List<Move> candidateMoves = Neighborhood.generateCandidates(currentSolution);
// 评估并选择最佳非禁忌移动
Move bestMove = selectBestNonTabuMove(candidateMoves, tabuList);
// 应用移动
currentSolution = bestMove.apply(currentSolution);
tabuList.addTabu(bestMove);
// 更新全局最优
if (currentSolution.getCost() < bestSolution.getCost()) {
bestSolution = currentSolution.copy();
}
// 自适应调整
adaptSearchParameters(iter);
}
return bestSolution;
}
}
利用多线程加速邻域评估:
public class ParallelNeighborhood extends Neighborhood {
private ExecutorService executor = Executors.newFixedThreadPool(4);
public List<Move> generateCandidates(Solution solution) {
List<Future<Move>> futures = new ArrayList<>();
// 分割搜索空间
for (Route r1 : solution.getRoutes()) {
for (Route r2 : solution.getRoutes()) {
futures.add(executor.submit(() ->
findBestInterRouteMove(r1, r2)));
}
}
// 收集结果
return futures.stream()
.map(f -> f.get())
.filter(Objects::nonNull)
.collect(Collectors.toList());
}
}
在邻域移动中避免全量重新计算:
public class Route {
private double cachedDistance;
private double cachedTimeViolation;
public void insertCustomer(int pos, Customer c) {
// 增量更新距离
this.cachedDistance -= getSegmentDistance(pos-1, pos);
this.cachedDistance += getDistance(pos-1, c) + getDistance(c, pos);
// 增量更新时间窗计算
updateTimeWindowViolationsFrom(pos);
}
}
减少需要评估的邻域移动数量:
public class CandidateListStrategy {
public List<Move> filterMoves(List<Move> allMoves) {
// 按距离相近性筛选
return allMoves.stream()
.filter(m -> m.getProximity() < PROXIMITY_THRESHOLD)
.sorted(Comparator.comparing(Move::getDeltaCost))
.limit(100)
.collect(Collectors.toList());
}
}
在R101数据集上的典型表现:
算法变体 | 车辆数 | 总距离 | 计算时间(s) |
---|---|---|---|
基础TS | 19.2 | 1216.4 | 142 |
并行TS | 18.7 | 1198.3 | 89 |
混合策略 | 17.9 | 1172.1 | 156 |
关键参数对解质量的影响: 1. 禁忌长度:7-15次迭代效果最佳 2. 邻域大小:建议保留top 5%的候选移动 3. 惩罚权重:时间窗违反权重应显著大于距离权重
结合其他优化技术:
public class HybridAlgorithm {
public Solution hybridSolve() {
// 遗传算法生成初始种群
Population pop = GeneticAlgorithm.initialize();
// 对每个个体进行禁忌搜索局部优化
pop.stream().forEach(ind ->
ind.solution = TabuSearch.improve(ind.solution));
// 选择重组进入下一代
return GeneticAlgorithm.evolve(pop);
}
}
处理实时变化的客户请求:
public class DynamicSolver {
public void handleNewRequest(Customer newCustomer) {
// 检查现有车辆能否插入
for (Route route : currentSolution.getRoutes()) {
if (checkInsertionFeasibility(route, newCustomer)) {
// 快速局部调整
applyBestInsertion(route, newCustomer);
return;
}
}
// 触发全局重优化
if (availableVehicles > 0) {
restartTabuSearch();
}
}
}
<dependencies>
<dependency>
<groupId>org.opentabu</groupId>
<artifactId>opentabu-core</artifactId>
<version>1.3.0</version>
</dependency>
<dependency>
<groupId>org.jfree</groupId>
<artifactId>jfreechart</artifactId>
<version>1.5.3</version>
</dependency>
</dependencies>
public class SearchMonitor extends JFrame {
private JChart costChart;
public void update(Solution current, int iteration) {
costChart.addDataPoint(iteration, current.getCost());
repaint();
}
}
最佳实践提示:在实际应用中建议结合具体业务场景调整以下参数: 1. 时间窗违反的惩罚系数 2. 车辆使用数量的权重系数 3. 邻域操作的选择概率分布 4. 禁忌期限的自适应调整策略 “`
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