java mongodb 项目 mongo-java-driver

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码海探险家 2023-08-03 15:24:10

文章标签 java mongodb 项目 java System 字段 文章分类 Java 后端开发

MongoDB的3.x版本Java驱动相对2.x做了全新的设计，类库和使用方法上有很大区别。例如用Document替换BasicDBObject、通过Builders类构建Bson替代直接输入$命令等，本文整理了基于3.2版本的常用增删改查操作的使用方法。为了避免冗长的篇幅，分为增删改、查询、聚合、地理索引等几部分。

创建一个maven项目，添加依赖

1. <dependencies>  
2.     <dependency>  
3.         <groupId>org.mongodb</groupId>  
4.         <artifactId>mongodb-driver</artifactId>  
5. 3.2.2</version>  
6.     </dependency>  
7. </dependencies>

非maven项目可自行下载jar包

http://central.maven.org/maven2/org/mongodb/mongo-java-driver/3.2.2/mongo-java-driver-3.2.2.jar

创建基础代码测试连接

1. public class CudExamples {  
2.   
3. public static void main(String[] args) throws ParseException {  
4. //根据实际环境修改ip和端口  
5. new MongoClient("localhost", 27017);  
6. "lesson");  
7.           
8. "language");  
9. //插入一个文档  
10. new Document("oop", "java"));  
11. new Document("oop", "java")));  
12.           
13.         mongoClient.close();  
14.     }  
15. }

如果输出结果为Document{{_id=573099877bee0e1710d52f4b, oop=java}}表示环境配置正确。

改造CudExamples类以方便演示每种操作对集合的影响


1. public class CudExamples {  
2.   
3. public static void main(String[] args) throws ParseException {  
4. new MongoClient("localhost", 27017);  
5. "lesson");  
6.           
7. new CudExamples(database);  
8.         client.show();  
9.         mongoClient.close();  
10.     }  
11.       
12. private MongoDatabase database;  
13. public CudExamples(MongoDatabase database) {  
14. this.database = database;  
15.     }  
16.       
17. public void show() {  
18. "language");  
19. //每次执行前清空集合以方便重复运行  
20.         mc.drop();  
21.           
22. new Document("oop", "java"));  
23. "insert java", mc);  
24.     }  
25.       
26. //打印查询的结果集  
27. public void printCollection(String doing, MongoCollection<Document> mc) {  
28.         System.out.println(doing);  
29.         FindIterable<Document> iterable = mc.find();  
30. new Block<Document>() {  
31. public void apply(final Document document) {  
32.                         System.out.println(document);  
33.                     }  
34.             });  
35. "------------------------------------------------------");  
36.             System.out.println();  
37.     }  
38. }

如上面代码所示，把所有的操作集中在show()方法中演示，并且在执行后打印集合以观察对集合的影响。下面来填充show()方法，注意需要静态导入Updates.*

import static com.mongodb.client.model.Updates.*;


1. mc.insertOne(new Document("oop", "java"));  
2. printCollection("insert java", mc);  
3.   
4. //插入一个包含两个字段的文档  
5. Document doc = new Document("oop", "csharp").append("copyright", "microsoft");  
6. mc.insertOne(doc);  
7. printCollection("insert csharp", mc);  
8.   
9. //查找并修改一个文档  
10. mc.findOneAndReplace(new Document("oop", "java"), new Document("oop", "java").append("copyright", "oracle"));  
11. printCollection("findAndReplace java", mc);  
12.   
13. //删除一个文档  
14. mc.deleteOne(new Document("oop", "java"));  
15. printCollection("delete java", mc);  
16.   
17. //删除全部文档  
18. mc.deleteMany(new Document());  
19. printCollection("delete all", mc);  
20.   
21. //重新插入测试文档  
22. mc.insertOne(new Document("oop", "java").append("copyright", "oracle"));  
23. mc.insertOne(new Document("oop", "csharp").append("copyright", "microsoft"));  
24. printCollection("insert java,csharp and swift", mc);  
25.   
26. //$set 文档中存在指定字段则修改,没有则添加  
27. mc.updateMany(new Document(), set("rank", 100));  
28. printCollection("$set all rank 100", mc);  
29.   
30. //$unset 文档中存在指定字段则删除该字段  
31. mc.updateOne(new Document("oop", "csharp"), unset("rank"));  
32. printCollection("unset csharp rank", mc);  
33.   
34. //$inc 文档中存在指定字段则相加,没有则添加  
35. mc.updateOne(new Document("oop", "csharp"), inc("rank", 30));  
36. printCollection("$inc csharp rank 30", mc);  
37. mc.updateOne(new Document("oop", "csharp"), inc("rank", 31));  
38. printCollection("$inc csharp rank 31", mc);  
39.   
40. //$setOnInsert 在更新时指定upsert=true并实际触发了插入操作时生效  
41. mc.updateOne(new Document("oop", "swift").append("copyright", "apple"), setOnInsert("rank", 100), new UpdateOptions().upsert(true));  
42. printCollection("$setOnInsert rank 100 for swift", mc);  
43.   
44. //$mul 相乘  
45. mc.updateOne(new Document("oop", "java"), mul("rank", 0.2));  
46. printCollection("$mul java rank: 0.2", mc);  
47.   
48. //$rename 重命名  
49. mc.updateMany(new Document(), rename("rank", "ranks"));  
50. printCollection("$rename all rank to ranks", mc);  
51.   
52. //$min 取当前值和指定值之间比较小的  
53. mc.updateMany(new Document(), min("ranks", 50));  
54. printCollection("$min all ranks: 50", mc);  
55.   
56. //$max 取当前值和指定值之间比较大的  
57. mc.updateMany(new Document(), max("ranks", 40));  
58. printCollection("$max all ranks: 40", mc);  
59.   
60. //$currentDate  
61. mc.updateMany(new Document("oop", "java"), currentDate("add"));  
62. printCollection("$currentDate java", mc);  
63.   
64. //$currentTimestamp  
65. mc.updateMany(new Document("oop", "java"), currentTimestamp("lastModified"));  
66. printCollection("$currentTimestamp java", mc);  
67.   
68. //$addToSet 添加一个元素到不重复集合  
69. mc.updateMany(new Document("oop", "java"), addToSet("keywords", "for"));  
70. mc.updateMany(new Document("oop", "java"), addToSet("keywords", "for"));  
71. printCollection("$addToSet java keywords: for", mc);  
72.   
73. //$addEachToSet 添加一组元素到不重复集合  
74. mc.updateMany(new Document("oop", "java"), addEachToSet("keywords", Arrays.asList("while", "true", "do", "new", "override")));  
75. mc.updateMany(new Document("oop", "java"), addEachToSet("keywords", Arrays.asList("while", "true", "do", "new", "override")));  
76. printCollection("$addEachToSet java keywords: while,true,do,new,override", mc);  
77.   
78. //$popFirst 删除第一个元素  
79. mc.updateMany(new Document("oop", "java"), popFirst("keywords"));  
80. printCollection("$popFirst java keywords", mc);  
81.   
82. //$popLast 删除最后一个元素  
83. mc.updateMany(new Document("oop", "java"), popLast("keywords"));  
84. printCollection("$popLast java keywords", mc);  
85.   
86. //$pull 删除指定元素  
87. mc.updateMany(new Document("oop", "java"), pull("keywords", "new"));  
88. printCollection("$pull java keywords: new", mc);  
89.   
90. //$pullByFilter 根据Filters删除  
91. mc.updateMany(new Document("oop", "java"), pullByFilter(Filters.gte("keywords", "true")));  
92. printCollection("$pullByFilter java keywords: true", mc);  
93.   
94. //$pullAll 删除一组元素  
95. mc.updateMany(new Document("oop", "java"), pullAll("keywords", Arrays.asList("while", "true", "do", "new", "override")));  
96. printCollection("$pullAll java keywords", mc);  
97.   
98. //$push 添加一个元素到可重复集合  
99. mc.updateMany(new Document("oop", "java"), push("scores", 89));  
100. printCollection("$push java scores: 89", mc);  
101.   
102. //$pushEach 添加一组元素到可重复集合  
103. mc.updateMany(new Document("oop", "java"), pushEach("scores", Arrays.asList(89, 90, 92)));  
104. printCollection("$pushEach java scores: 89,90,92", mc);  
105.   
106. //在集合的指定位置插入一组元素  
107. mc.updateMany(new Document("oop", "java"), pushEach("scores", Arrays.asList(11, 12, 13), new PushOptions().position(0)));  
108. printCollection("$pushEach java scores: 11,12,13 at position 0", mc);  
109.   
110. //在集合的指定位置插入一组元素并倒序排列  
111. mc.updateMany(new Document("oop", "java"), pushEach("scores", Arrays.asList(40, 41), new PushOptions().sort(-1)));  
112. printCollection("$pushEach java scores: 40,41 and sort(-1)", mc);  
113.   
114. //在集合的指定位置插入一组元素, 倒序排列后保留前3个  
115. mc.updateMany(new Document("oop", "java"), pushEach("scores", Arrays.asList(60, 61), new PushOptions().sort(-1).slice(3)));  
116. printCollection("$pushEach java scores: 60,61 and sort(-1) and slice(3)", mc);  
117.   
118. //插入一组内嵌文档  
119. Bson bson = pushEach("experts",  
120. new Document("first", "Rod").append("last", "Johnson"),  
121. new Document("first", "Doug").append("last", "Cutting")));  
122. mc.updateOne(new Document("oop", "java"), bson);  
123. printCollection("$pushEach", mc);  
124.   
125. //combine 组合Bson  
126. bson = combine(set("author", "James Gosling"), set("version", "8.0"));  
127. mc.updateOne(new Document("oop", "java"), bson);  
128. printCollection("$combine", mc);

(完)

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