spring-batch

问题 I have a requirement to get the data from a database and write that data to files based on the filename given in the database. This is how data is defined in the database: Columns --> FILE_NAME, REC_ID, NAME Data --> file_1.csv, 1, ABC Data --> file_1.csv, 2, BCD Data --> file_1.csv, 3, DEF Data --> file_2.csv, 4, FGH Data --> file_2.csv, 5, DEF Data --> file_3.csv, 6, FGH Data --> file_3.csv, 7, DEF Data --> file_4.csv, 8, FGH As you see, basically the file names along with the data is

问题 Whats the relationship/difference between Spring-Batch Reader 'pageSize' property and Writer 'commit-interval'. I may be wrong but I see a pattern in my application that for every pageSize exceeded I get see one commit being made. Is this true.? Thanks 回答1: The commit-interval defines how many items are processed within a single chunk. That number of items are read, processed, then written within the scope of a single transaction (skip/retry semantics not withstanding). The page-size

问题 Scenario To make it simple, let's suppose I have an ItemReader that returns me 25 rows. The first 10 rows belong to student A The next 5 belong to student B and the 10 remaining belong to student C I want to aggregate them together logically say by studentId and flatten them to end up with one row per student. Problem If I understand correctly, setting the commit interval to 5 will do the following: Send 5 rows to the Processor (which will aggregate them or do any business logic I tell it to)

问题 I have a file to parse and process records from. It is working fine as line-by-line (parsing one record at a time). My requirement is I've to parse thru multiple line and fetch the required information from each records and then after combining the fetched info from all the records, I call a service to perform business logic. I have to perform this logic inside my Processor class. The data looks like as below example: 001 123456 987654321551580 Wayne DR 1 001 123456 987654321552APT 786 1 001

问题 I 'm using Spring Batch(3.0.1.RELEASE) / JPA and an HSQLBD server database. I need to browse an entire table (using paging) and update items (one by one). So I used a jpaPagingItemReader. But when I run the job I can see that some rows are skipped, and the number of skipped rows is equal to the page size. For i.e. if my table has 12 rows and the jpaPagingItemReader.pagesize = 3 the job will read : lines 1,2,3 then lines 7,8,9 (so skip the lines 4,5,6)… Could you tell me what is wrong in my

问题 Say my commit interval is 1000. And during writing I get a error at 990th record which is skippable as per skip policy. So a rollback will occur and the writer will start again writing the same records from record 1. However, this time, It is commiting on each record. It does not honour commit interval. This is making the job dead slow. Why the behavior is like that ?? Am I missing something in my configuration ?? Thanks. 回答1: that bevaviour is mandatory for spring batch to isolate the bad

问题 Thanks for attention i used spring integration in my project, i want to retrieve many input file from multiple ftp server with different address as bellow image: how to create dynamically inbound-adapter in my project to polling and retrieve files from servers? 回答1: See the dynamic-ftp sample. While it only covers the outbound side, there are links in the README to discussions about what needs to be done on the inbound side (put each adapter in a child context that send messages to a channel

问题 I am migrating Spring Boot from 1.4.2 to 2.0.0, which also includes migrating Spring batch from 3.0.7 to 4.0.0 and it looks like batch process is no longer working when i try to run it with new Spring Batch version. When I tried to debug i found a problem when batch tries to get data from batch_job_execution_context. I can see the getting the data from database works fine, but the new version of batch fails to parse database data {"map":[{"entry":[{"string":["name",""]},{"string":["sender",""

问题 I am migrating Spring Boot from 1.4.2 to 2.0.0, which also includes migrating Spring batch from 3.0.7 to 4.0.0 and it looks like batch process is no longer working when i try to run it with new Spring Batch version. When I tried to debug i found a problem when batch tries to get data from batch_job_execution_context. I can see the getting the data from database works fine, but the new version of batch fails to parse database data {"map":[{"entry":[{"string":["name",""]},{"string":["sender",""

问题 I want to write an SQL for SqlPagingQueryProviderFactoryBean. I will pass the parameter for an IN clause. I am not getting the result when I am passing it as a parameter(?). But I am getting the correct result when I am hard coding the values. Please guide me on this. 回答1: You cannot have a single place holder and replace it with an array due to sql injection security policy, However the gettter/setters of sqlPagingQueryProvider properties selectclause, fromClause and whereCLause are String