我已经尝试了很长时间使用Java上传文件至Google云存储。通过谷歌搜索,我找到了以下代码,但是无法完全理解。请问有人能够定制这段代码以实现向GCS上传文件吗?
// Given
InputStream inputStream; // object data, e.g., FileInputStream
long byteCount; // size of input stream
InputStreamContent mediaContent = new InputStreamContent("application/octet-stream", inputStream);
// Knowing the stream length allows server-side optimization, and client-side progress
// reporting with a MediaHttpUploaderProgressListener.
mediaContent.setLength(byteCount);
StorageObject objectMetadata = null;
if (useCustomMetadata) {
// If you have custom settings for metadata on the object you want to set
// then you can allocate a StorageObject and set the values here. You can
// leave out setBucket(), since the bucket is in the insert command's
// parameters.
objectMetadata = new StorageObject()
.setName("myobject")
.setMetadata(ImmutableMap.of("key1", "value1", "key2", "value2"))
.setAcl(ImmutableList.of(
new ObjectAccessControl().setEntity("domain-example.com").setRole("READER"),
new ObjectAccessControl().setEntity("user-administrator@example.com").setRole("OWNER")
))
.setContentDisposition("attachment");
}
Storage.Objects.Insert insertObject = storage.objects().insert("mybucket", objectMetadata,
mediaContent);
if (!useCustomMetadata) {
// If you don't provide metadata, you will have specify the object
// name by parameter. You will probably also want to ensure that your
// default object ACLs (a bucket property) are set appropriately:
// https://developers.google.com/storage/docs/json_api/v1/buckets#defaultObjectAcl
insertObject.setName("myobject");
}
// For small files, you may wish to call setDirectUploadEnabled(true), to
// reduce the number of HTTP requests made to the server.
if (mediaContent.getLength() > 0 && mediaContent.getLength() <= 2 * 1000 * 1000 /* 2MB */) {
insertObject.getMediaHttpUploader().setDirectUploadEnabled(true);
}
insertObject.execute();