Write Operations

Filters

You can pass in a filter document to the methods to specify which documents to update. The filter document specification is the same as for read operations. To facilitate the creation of filter objects, the driver provides the Filters helper class.

To specify an empty filter and match all documents in a collection, use an empty Document object as the filter.

Update Operators

To change a field in a document, MongoDB provides update operators. To specify the modification to perform using the update operators, create an update document. To learn more about update operators, see Update Operators in the Server manual.

To facilitate the creation of update documents, the driver provides the Updates helper class.

Update a Single Document

The updateOne() method updates a single document, even if the filter condition matches multiple documents in the collection.

The following operation on the restaurants collection updates a document in which the value of the id field is ObjectId("57506d62f57802807471dd41"):

collection.updateOne(
    eq("_id", new ObjectId("57506d62f57802807471dd41")),
    combine(set("stars", 1), set("contact.phone", "228-555-9999"), currentDate("lastModified"))
).subscribe(new ObservableSubscriber<UpdateResult>());

Specifically, the operation uses the following methods:

• Updates.set() to set the value of the stars field to 1 and the contact.phone field to "228-555-9999"

• Updates.currentDate() to modify the lastModified field to the current date. If the lastModified field does not exist, the operator adds the field to the document.

Update Multiple Documents

The updateMany() method updates all documents that match the filter condition.

The following operation on the restaurants collection updates all documents in which the value of the stars field is 2:

collection.updateMany(
    eq("stars", 2),
    combine(set("stars", 0), currentDate("lastModified"))
).subscribe(new ObservableSubscriber<UpdateResult>());

Specifically, the operation uses the following methods:

• Updates.set() to set the value of the stars field to 0

• Updates.currentDate() to set the lastModified field to the current date. If the lastModified field does not exist, the operator adds the field to the document.

Update Options

When using the updateOne() and updateMany() methods, you can include an UpdateOptions document to specify the upsert option or the bypassDocumentationValidation option:

collection.updateOne(
    eq("_id", 1),
    combine(set("name", "Fresh Breads and Tulips"), currentDate("lastModified")),
    new UpdateOptions().upsert(true).bypassDocumentValidation(true)
).subscribe(new ObservableSubscriber<UpdateResult>());

Filters

You can pass in a filter document to the replaceOne() method to specify which document to replace. The filter document specification is the same as for read operations. To facilitate the creation of filter objects, the driver provides the Filters helper class.

To specify an empty filter and match all documents in a collection, use an empty Document object as the filter.

The replaceOne() method replaces at most a single document, even if the filter condition matches multiple documents in the collection.

Replace a Document

To replace a document, pass a new document to the replaceOne() method.

The following operation on the restaurants collection replaces the document in which the value of the id field is ObjectId("57506d62f57802807471dd41"):

collection.replaceOne(
    eq("_id", new ObjectId("57506d62f57802807471dd41")),
    new Document("name", "Green Salads Buffet")
        .append("contact", "TBD")
        .append("categories", Arrays.asList("Salads", "Health Foods", "Buffet"))
).subscribe(new ObservableSubscriber<UpdateResult>());

Update Options

When using the replaceOne() method, you can include an UpdateOptions document to specify the upsert option or the bypassDocumentationValidation option:

collection.replaceOne(
    eq("name", "Orange Patisserie and Gelateria"),
    new Document("stars", 5)
        .append("contact", "TBD")
        .append("categories", Arrays.asList("Cafe", "Pastries", "Ice Cream")),
    new UpdateOptions().upsert(true).bypassDocumentValidation(true)
).subscribe(new ObservableSubscriber<UpdateResult>());

Filters

You can pass in a filter document to the methods to specify which documents to delete. The filter document specification is the same as for read operations. To facilitate the creation of filter objects, the driver provides the Filters helper class.

To specify an empty filter and match all documents in a collection, use an empty Document object as the filter.

Delete a Single Document

The deleteOne() method deletes at most a single document, even if the filter condition matches multiple documents in the collection.

The following operation on the restaurants collection deletes a document in which the value of the _id field is ObjectId("57506d62f57802807471dd41"):

collection
    .deleteOne(eq("_id", new ObjectId("57506d62f57802807471dd41")))
    .subscribe(new ObservableSubscriber<DeleteResult>());

Delete Multiple Documents

The deleteMany() method deletes all documents that match the filter condition.

The following operation on the restaurants collection deletes all documents in which the value of the stars field is 4:

collection
    .deleteMany(eq("stars", 4))
    .subscribe(new ObservableSubscriber<DeleteResult>());