Analyze API
editAnalyze API
editAnalyze Request
editAn AnalyzeRequest
contains the text to analyze, and one of several options to
specify how the analysis should be performed.
The simplest version uses a built-in analyzer:
AnalyzeRequest request = new AnalyzeRequest(); request.text("Some text to analyze", "Some more text to analyze"); request.analyzer("english");
You can configure a custom analyzer:
AnalyzeRequest request = new AnalyzeRequest(); request.text("<b>Some text to analyze</b>"); request.addCharFilter("html_strip"); request.tokenizer("standard"); request.addTokenFilter("lowercase"); Map<String, Object> stopFilter = new HashMap<>(); stopFilter.put("type", "stop"); stopFilter.put("stopwords", new String[]{ "to" }); request.addTokenFilter(stopFilter);
Configure char filters |
|
Configure the tokenizer |
|
Add a built-in tokenfilter |
|
Configuration for a custom tokenfilter |
|
Add the custom tokenfilter |
You can also build a custom normalizer, by including only charfilters and tokenfilters:
AnalyzeRequest request = new AnalyzeRequest(); request.text("<b>BaR</b>"); request.addTokenFilter("lowercase");
You can analyze text using an analyzer defined in an existing index:
AnalyzeRequest request = new AnalyzeRequest(); request.index("my_index"); request.analyzer("my_analyzer"); request.text("some text to analyze");
Or you can use a normalizer:
AnalyzeRequest request = new AnalyzeRequest(); request.index("my_index"); request.normalizer("my_normalizer"); request.text("some text to analyze");
You can analyze text using the mappings for a particular field in an index:
AnalyzeRequest request = new AnalyzeRequest(); request.index("my_index"); request.field("my_field"); request.text("some text to analyze");
Optional arguments
editThe following arguments can also optionally be provided:
Synchronous Execution
editWhen executing a AnalyzeRequest
in the following manner, the client waits
for the AnalyzeResponse
to be returned before continuing with code execution:
AnalyzeResponse response = client.indices().analyze(request, RequestOptions.DEFAULT);
Synchronous calls may throw an IOException
in case of either failing to
parse the REST response in the high-level REST client, the request times out
or similar cases where there is no response coming back from the server.
In cases where the server returns a 4xx
or 5xx
error code, the high-level
client tries to parse the response body error details instead and then throws
a generic ElasticsearchException
and adds the original ResponseException
as a
suppressed exception to it.
Asynchronous Execution
editExecuting a AnalyzeRequest
can also be done in an asynchronous fashion so that
the client can return directly. Users need to specify how the response or
potential failures will be handled by passing the request and a listener to the
asynchronous analyze method:
The asynchronous method does not block and returns immediately. Once it is
completed the ActionListener
is called back using the onResponse
method
if the execution successfully completed or using the onFailure
method if
it failed. Failure scenarios and expected exceptions are the same as in the
synchronous execution case.
A typical listener for analyze
looks like:
Analyze Response
editThe returned AnalyzeResponse
allows you to retrieve details of the analysis as
follows:
If explain
was set to true
, then information is instead returned from the detail()
method: