java调用milvus数据库

package org.dromara.langchain4j.config;

import io.milvus.client.MilvusServiceClient;
import io.milvus.grpc.DataType;
import io.milvus.grpc.MutationResult;
import io.milvus.grpc.SearchResults;
import io.milvus.param.*;
import io.milvus.param.collection.CreateCollectionParam;
import io.milvus.param.collection.FieldType;
import io.milvus.param.collection.LoadCollectionParam;
import io.milvus.param.dml.InsertParam;
import io.milvus.param.dml.SearchParam;
import io.milvus.param.index.CreateIndexParam;
import io.milvus.response.QueryResultsWrapper;
import io.milvus.response.SearchResultsWrapper;

import java.util.*;

public class MilvusJavaDemo {

    // 1. 连接Milvus服务器
    private static MilvusServiceClient connectMilvus() {
        String uri = "http://localhost:19530"; // Milvus服务地址
        ConnectParam connectParam = ConnectParam.newBuilder()
                .withUri(uri)
                .build();
        return new MilvusServiceClient(connectParam);
    }

    public static void main(String[] args) {
        MilvusServiceClient client = connectMilvus();
        final String COLLECTION_NAME = "book_collection";
        final int VECTOR_DIM = 768; // 向量维度

        try {
            // 4. 加载集合到内存（搜索前必须步骤）
            R<RpcStatus> loadRes = client.loadCollection(LoadCollectionParam.newBuilder()
                    .withCollectionName(COLLECTION_NAME)
                    .build());

            // 5. 插入数据（增 - Create）
            Random ran = new Random();
            // 6. 执行向量相似性搜索（查 - Read/Query）
            // 准备一个随机向量作为查询目标
            List<Float> targetVector = new ArrayList<>();
            for (int i = 0; i < VECTOR_DIM; i++) {
                targetVector.add(ran.nextFloat());
            }
            List<List<Float>> searchVectors = Arrays.asList(targetVector);

            SearchParam searchParam = SearchParam.newBuilder()
                    .withCollectionName(COLLECTION_NAME)
                    .withVectorFieldName("book_intro")
                    .withVectors(searchVectors)
                    .withTopK(2) // 返回最相似的2条结果
                    .withMetricType(MetricType.L2)
                    .withParams("{\"nprobe\":10}") // 搜索参数
                    .addOutField("word_count") // 指定返回的标量字段
                    .build();

            R<SearchResults> searchRes = client.search(searchParam);
            if (searchRes.getStatus() == R.Status.Success.getCode()) {
                SearchResultsWrapper wrapper = new SearchResultsWrapper(searchRes.getData().getResults());
                System.out.println("\n搜索完成，结果如下：");
                for (QueryResultsWrapper.RowRecord results : wrapper.getRowRecords()) {
//                    System.out.printf("距离: %f, 数据: %s%n", results.getFieldValues(), record.getFields());
                    Map<String, Object> fieldValues = results.getFieldValues();
                    for (Map.Entry<String, Object> entry : fieldValues.entrySet()) {
                        System.out.println(entry.getKey() + ": " + entry.getValue());
                    }
                }
            }

            // 7. 删除数据（删 - Delete）
            // 构建删除表达式，例如删除 word_count < 9000 的记录
//            String deleteExpr = "word_count < 9000";
//            DeleteParam deleteParam = DeleteParam.newBuilder()
//                    .withCollectionName(COLLECTION_NAME)
//                    .withExpr(deleteExpr)
//                    .build();
//            R<MutationResult> deleteRes = client.delete(deleteParam);
//            long deleteCount = deleteRes.getData().getDeleteCnt();
//            System.out.println("\n删除操作完成，删除了 " + deleteCount + " 条记录。");

        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            // 8. 可选：删除集合（清理环境）
            // R<RpcStatus> dropRes = client.dropCollection(DropCollectionParam.newBuilder()
            //         .withCollectionName(COLLECTION_NAME)
            //         .build());
            // System.out.println("集合已删除。");

            // 关闭客户端连接
            client.close();
        }
    }
}