elasticsearch httpClient3.x bulk api - elasticsearch

Question

I use httpClient3.x to _bulk operator the elasticsearch 4.5.1 restful api:
postUrl = "http://127.0.0.1:9200/_bulk";
postMethod = new PostMethod(postUrl);
query = "{\"delete\":{\"_index\":\"equipment\", \"_type\":\"unit\", \"_id\":\"3\" } }" + "\n";
System.out.println("query ="+query);
requestEntity = new StringRequestEntity(query,
"application/x-ndjson", "UTF-8");
postMethod.setRequestEntity(requestEntity);
statusCode = httpClient.executeMethod(postMethod);
postMethod.getResponseBodyAsStream();
System.out.println("Bulk Response status code: " + statusCode);
System.out.println("Bulk Response body: ");
System.out.println(postMethod.getResponseBodyAsString());
the console return:
query ={"delete":{"_index":"equipment", "_type":"unit", "_id":"3" } }
Bulk Response status code: 400
Bulk Response body:
{"error":{"root_cause":[{"type":"parsing_exception","reason":"Unknown key for a START_OBJECT in [delete].","line":1,"col":11}],"type":"parsing_exception","reason":"Unknown key for a START_OBJECT in [delete].","line":1,"col":11},"status":400}
when i paste the blow code in Kibana,it return "status": 200
POST _bulk
{
"delete": {
"_index": "equipment",
"_type": "unit",
"_id": "1"
}
}
does it because the HttpClient3.x does't support x-ndjson or the query format is wrong or other resons? how can it run _bulk api successfully in HttpClient3.x
Result
2017/08/02 14:29:49:571 CST [DEBUG] HttpClient - Java version: 1.7.0_79
2017/08/02 14:29:49:575 CST [DEBUG] HttpClient - Java vendor: Oracle Corporation
2017/08/02 14:29:49:575 CST [DEBUG] HttpClient - Java class path: /Users/qk/Documents/workspace-luna/httpclient-test/bin:/Users/qk/Documents/workspace-luna/httpclient-test/lib/commons-beanutils.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/commons-codec-1.10.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/commons-collections4-4.1.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/commons-httpclient.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/commons-lang.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/commons-logging-1.1.3.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/ezmorph-1.0.5.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/json-lib-2.2-jdk15.jar:/Users/qk/Documents/workspace-luna/httpclient-test/lib/morph-1.1.1.jar
2017/08/02 14:29:49:575 CST [DEBUG] HttpClient - Operating system name: Mac OS X
2017/08/02 14:29:49:575 CST [DEBUG] HttpClient - Operating system architecture: x86_64
2017/08/02 14:29:49:575 CST [DEBUG] HttpClient - Operating system version: 10.11.6
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SUN 1.7: SUN (DSA key/parameter generation; DSA signing; SHA-1, MD5 digests; SecureRandom; X.509 certificates; JKS keystore; PKIX CertPathValidator; PKIX CertPathBuilder; LDAP, Collection CertStores, JavaPolicy Policy; JavaLoginConfig Configuration)
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SunRsaSign 1.7: Sun RSA signature provider
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SunEC 1.7: Sun Elliptic Curve provider (EC, ECDSA, ECDH)
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SunJSSE 1.7: Sun JSSE provider(PKCS12, SunX509 key/trust factories, SSLv3, TLSv1)
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SunJCE 1.7: SunJCE Provider (implements RSA, DES, Triple DES, AES, Blowfish, ARCFOUR, RC2, PBE, Diffie-Hellman, HMAC)
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SunJGSS 1.7: Sun (Kerberos v5, SPNEGO)
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SunSASL 1.7: Sun SASL provider(implements client mechanisms for: DIGEST-MD5, GSSAPI, EXTERNAL, PLAIN, CRAM-MD5, NTLM; server mechanisms for: DIGEST-MD5, GSSAPI, CRAM-MD5, NTLM)
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - XMLDSig 1.0: XMLDSig (DOM XMLSignatureFactory; DOM KeyInfoFactory)
2017/08/02 14:29:49:635 CST [DEBUG] HttpClient - SunPCSC 1.7: Sun PC/SC provider
2017/08/02 14:29:49:636 CST [DEBUG] HttpClient - Apple 1.1: Apple Provider
2017/08/02 14:29:49:639 CST [DEBUG] DefaultHttpParams - Set parameter http.useragent = Jakarta Commons-HttpClient/3.1
2017/08/02 14:29:49:641 CST [DEBUG] DefaultHttpParams - Set parameter http.protocol.version = HTTP/1.1
2017/08/02 14:29:49:642 CST [DEBUG] DefaultHttpParams - Set parameter http.connection-manager.class = class org.apache.commons.httpclient.SimpleHttpConnectionManager
2017/08/02 14:29:49:642 CST [DEBUG] DefaultHttpParams - Set parameter http.protocol.cookie-policy = default
2017/08/02 14:29:49:642 CST [DEBUG] DefaultHttpParams - Set parameter http.protocol.element-charset = US-ASCII
2017/08/02 14:29:49:642 CST [DEBUG] DefaultHttpParams - Set parameter http.protocol.content-charset = ISO-8859-1
2017/08/02 14:29:49:643 CST [DEBUG] DefaultHttpParams - Set parameter http.method.retry-handler = org.apache.commons.httpclient.DefaultHttpMethodRetryHandler#2972a4d0
2017/08/02 14:29:49:644 CST [DEBUG] DefaultHttpParams - Set parameter http.dateparser.patterns = [EEE, dd MMM yyyy HH:mm:ss zzz, EEEE, dd-MMM-yy HH:mm:ss zzz, EEE MMM d HH:mm:ss yyyy, EEE, dd-MMM-yyyy HH:mm:ss z, EEE, dd-MMM-yyyy HH-mm-ss z, EEE, dd MMM yy HH:mm:ss z, EEE dd-MMM-yyyy HH:mm:ss z, EEE dd MMM yyyy HH:mm:ss z, EEE dd-MMM-yyyy HH-mm-ss z, EEE dd-MMM-yy HH:mm:ss z, EEE dd MMM yy HH:mm:ss z, EEE,dd-MMM-yy HH:mm:ss z, EEE,dd-MMM-yyyy HH:mm:ss z, EEE, dd-MM-yyyy HH:mm:ss z]
query ={"delete":{"_index":"equipment", "_type":"unit", "_id":"2" } }
2017/08/02 14:29:49:692 CST [DEBUG] HttpConnection - Open connection to 127.0.0.1:9200
2017/08/02 14:29:49:707 CST [DEBUG] header - >> "POST /_bulk HTTP/1.1[\r][\n]"
2017/08/02 14:29:49:707 CST [DEBUG] HttpMethodBase - Adding Host request header
2017/08/02 14:29:49:719 CST [DEBUG] header - >> "User-Agent: Jakarta Commons-HttpClient/3.1[\r][\n]"
2017/08/02 14:29:49:719 CST [DEBUG] header - >> "Host: 127.0.0.1:9200[\r][\n]"
2017/08/02 14:29:49:719 CST [DEBUG] header - >> "Content-Length: 63[\r][\n]"
2017/08/02 14:29:49:719 CST [DEBUG] header - >> "Content-Type: application/x-ndjson; charset=UTF-8[\r][\n]"
2017/08/02 14:29:49:720 CST [DEBUG] header - >> "[\r][\n]"
2017/08/02 14:29:49:720 CST [DEBUG] content - >> "{"delete":{"_index":"equipment", "_type":"unit", "_id":"2" } }[\n]"
2017/08/02 14:29:49:720 CST [DEBUG] EntityEnclosingMethod - Request body sent
2017/08/02 14:29:49:735 CST [DEBUG] header - << "HTTP/1.1 200 OK[\r][\n]"
2017/08/02 14:29:49:735 CST [DEBUG] header - << "HTTP/1.1 200 OK[\r][\n]"
2017/08/02 14:29:49:736 CST [DEBUG] header - << "Warning: 299 Elasticsearch-5.4.1-2cfe0df "Content type detection for rest requests is deprecated. Specify the content type using the [Content-Type] header." "Wed, 02 Aug 2017 06:29:49 GMT"[\r][\n]"
2017/08/02 14:29:49:736 CST [DEBUG] header - << "content-type: application/json; charset=UTF-8[\r][\n]"
2017/08/02 14:29:49:736 CST [DEBUG] header - << "content-length: 203[\r][\n]"
2017/08/02 14:29:49:737 CST [DEBUG] header - << "[\r][\n]"
Bulk Response status code: 200
Bulk Response body:
2017/08/02 14:29:49:737 CST [DEBUG] HttpMethodBase - Buffering response body
2017/08/02 14:29:49:738 CST [DEBUG] content - << "{"took":1,"errors":false,"items":[{"delete":{"found":false,"_index":"equipment","_type":"unit","_id":"2","_version":3,"result":"not_found","_shards":{"total":2,"successful":1,"failed":0},"status":404}}]}"
2017/08/02 14:29:49:738 CST [DEBUG] HttpMethodBase - Resorting to protocol version default close connection policy
2017/08/02 14:29:49:738 CST [DEBUG] HttpMethodBase - Should NOT close connection, using HTTP/1.1
2017/08/02 14:29:49:738 CST [DEBUG] HttpConnection - Releasing connection back to connection manager.
{"took":1,"errors":false,"items":[{"delete":{"found":false,"_index":"equipment","_type":"unit","_id":"2","_version":3,"result":"not_found","_shards":{"total":2,"successful":1,"failed":0},"status":404}}]}