问题
I am looking to create a physical copy of a sub type of dm_document using the DCTM REST API. I am pretty new to the DCTM world, especially when it comes to the REST API.
The use case that I have is when a certain action happens, I need to clone the document (meta & content) and alter 1 or 2 pieces of meta and save that new document back the repository.
I have reviewed all the examples located here: https://community.emc.com/docs/DOC-34346 however, I am unable to figure out how to retrieve the document & content using this example (Spring Rest) having just the r_object_id. I have used this example to create content, therefore if I could just download the content & meta to my application, I could do the rest. However no matter what I try - I can't seem to get the data using the r_object_id.
If anyone could provide a pointer, it would help me out a lot.
Thanks.
回答1:
Here is how you get the object information, and it's content. I really wanted to know how to do these things too so i tried hard and finally got it fully working.
For making the request you will need to use xmlconfigeditor.jar from documentum. Other base64 encodings are not working...
I used java-json.jar for easy use of the jsons. It is not a "must" have. But it will help you a lot. Otherwise you will need to read the json string yourself.
I used @Eddie 's answer from Java: Reading a pdf file from URL into Byte array/ByteBuffer in an applet to get the file from url as byte array.
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.nio.ByteBuffer;
import org.apache.http.HttpEntity;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.json.JSONArray;
import org.json.JSONObject;
public class test {
public static void main(String[] args) throws Exception {
String repository_name = "";
String r_object_id = "";
JSONObject theObject = makeRequest("http://localhost:8000/dctm-rest/repositories/"
+ repository_name + "/objects/" + r_object_id);
if (theObject != null) {
// you have all information about the object now
// you can access the attributes of the object by
// theObject.getJSONObject("properties") then like
// .getString("object_name")
JSONObject contentJSON = makeRequest("http://localhost:8000/dctm-rest/repositories/"
+ repository_name
+ "/objects/"
+ r_object_id
+ "/contents/content");
JSONArray js = contentJSON.getJSONArray("links");
for (int i = 0; i < js.length(); i++) {
JSONObject jo = js.getJSONObject(i);
if (jo.has("title") && "ACS".equals(jo.getString("title"))) {
// here is your byte array
byte[] bytes = getAsByteArray(new URL(jo.getString("href")))
.array();
}
}
}
}
public static JSONObject makeRequest(String url) {
JSONObject json = null;
String username = "";
String password = "";
String strResponse = "";
CloseableHttpClient httpClient = HttpClientBuilder.create().build();
BufferedReader rd = null;
CloseableHttpResponse cls = null;
HttpGet request = new HttpGet(url);
RequestConfig config = RequestConfig.custom()
.setSocketTimeout(120 * 1000).setConnectTimeout(30 * 1000)
.setConnectionRequestTimeout(30 * 1000).build();
request.setConfig(config);
request.addHeader("Accept", "application/vnd.emc.documentum+json");
request.addHeader(
"Authorization",
"Basic "
+ com.documentum.xmlconfig.util.Base64.encode(username
+ ":" + password));
try {
cls = httpClient.execute(request);
HttpEntity entity = cls.getEntity();
rd = new BufferedReader(new InputStreamReader(entity.getContent()));
String line = "";
while (line != null) {
line = rd.readLine();
strResponse += line;
}
strResponse = strResponse.trim().replace("\n", "");
String statusline = cls.getStatusLine().toString();
if (!statusline.contains("200") && !statusline.contains("201")) {
System.out.println(strResponse);
} else {
json = new JSONObject(strResponse);
}
} catch (Exception e) {
e.printStackTrace();
}
return json;
}
public static ByteBuffer getAsByteArray(URL url) throws IOException {
URLConnection connection = url.openConnection();
// Since you get a URLConnection, use it to get the InputStream
InputStream in = connection.getInputStream();
// Now that the InputStream is open, get the content length
int contentLength = connection.getContentLength();
// To avoid having to resize the array over and over and over as
// bytes are written to the array, provide an accurate estimate of
// the ultimate size of the byte array
ByteArrayOutputStream tmpOut;
if (contentLength != -1) {
tmpOut = new ByteArrayOutputStream(contentLength);
} else {
tmpOut = new ByteArrayOutputStream(16384); // Pick some appropriate
// size
}
byte[] buf = new byte[512];
while (true) {
int len = in.read(buf);
if (len == -1) {
break;
}
tmpOut.write(buf, 0, len);
}
in.close();
tmpOut.close(); // No effect, but good to do anyway to keep the metaphor
// alive
byte[] array = tmpOut.toByteArray();
// Lines below used to test if file is corrupt
// FileOutputStream fos = new FileOutputStream("C:\\abc.pdf");
// fos.write(array);
// fos.close();
return ByteBuffer.wrap(array);
}
}
来源：https://stackoverflow.com/questions/34158219/how-can-i-use-rest-to-copy-an-object-in-documentum-7-x