* This is a very simple class that will submit an XQuery string to the server and return the * result. *
** Click here for the source code for this class *
** The main() method looks for two command-line args, a URL for the server ( * {@link ContentSourceFactory#newContentSource(java.net.URI)}) and a filename to read a query from. * It loads the file, submits its contents to the server for evaluation and then prints the result * sequence to stdout, one item per line. *
** The class has methods the could be used to set request options and to obtain the results as an * array of Strings or as a real {@link ResultSequence}. *
** If you want to set external variables for a request, you can call {@link #getRequest()} to obtain * a reference to the internal {@link Request} object and set the variable values on it before * invoking {@link #execute(String)}. *
*/ public class SimpleQueryRunner { private final Session session; private final AdhocQuery request; private RequestOptions options; /** * Construct an instance that will submit query requests to the server represented by the given * URI. Note that the URI will not be validated at this time. * * @param serverUri * A URI that specifies a server per ( * {@link ContentSourceFactory#newContentSource(java.net.URI)}). * @throws XccConfigException * If the URI is not a valid XCC server URL. */ public SimpleQueryRunner(URI serverUri) throws XccConfigException { ContentSource cs = ContentSourceFactory.newContentSource(serverUri); session = cs.newSession(); request = session.newAdhocQuery(null); } /** * Submit the given query string and return a {@link ResultSequence} object. * * @param query * XQuery code as a String, to be evaluated by the server. * @return An instance {@link ResultSequence}, possibly with size zero. * @throws RequestException * If an unrecoverable error occurs when submitting or evaluating the request. */ public ResultSequence execute(String query) throws RequestException { request.setQuery(query); request.setOptions(options); return session.submitRequest(request); } /** * Submit the given query string and return an array of Strings, possibly of length zero, which * contains the String value of each {@link ResultItem} (see * {@link com.marklogic.xcc.ResultItem#asString()}) * * @param query * XQuery code as a String, to be evaluated by the server. * @return An array of Strings, one per item in the {@link ResultSequence}. * @throws RequestException * If an unrecoverable error occurs when submitting or evaluating the request. */ public String[] executeToStringArray(String query) throws RequestException { ResultSequence rs = execute(query); return rs.asStrings(); } /** * Submit the given query string and return a single String which is the concatenation of all * the {@link ResultItem}s, separated by the given separator string. * * @param query * XQuery code as a String, to be evaluated by the server. * @param separator * A String value which will be inserted in the final string between each item of the * sequence. A value of null is equivalent to the empty string. * @return A String consisting of the {@link com.marklogic.xcc.ResultItem#asString()} value of * each item with the separator string inserted between each instance. * @throws RequestException * If an unrecoverable error occurs when submitting or evaluating the request. */ public String executeToSingleString(String query, String separator) throws RequestException { ResultSequence rs = execute(query); String str = rs.asString(separator); rs.close(); return str; } /** * Returns the {@link Request} object used internally to submit requests. This object can be * used to set external variables that will be bound to the query when submitted. You should not * set your own {@link RequestOptions} object, use * {@link #setRequestOptions(com.marklogic.xcc.RequestOptions)} instead. * * @return An instance of {@link Request}. */ public Request getRequest() { return request; } /** * Set (or clear) the {@link RequestOptions} instance to associate with submitted queries. * * @param options * An instance of {@link RequestOptions} or null. */ public void setRequestOptions(RequestOptions options) { this.options = options; } // ----------------------------------------------------- /** * Simple command-line driver that will read a query from a file and submit it to the server at * the given URL. No validation of the query file is done to insure that it really is XQuery or * that it's a reasonable size. * * @param args * First arg: a URL as per * {@link ContentSourceFactory#newContentSource(java.net.URI)}. Second arg: a * filename to read XQuery text from. * @throws Exception * No exceptions are handled, anything that goes wrong will spew out a stack trace * and exit. */ public static void main(String[] args) throws Exception { if (args.length < 2) { usage(); return; } URI serverUri = new URI(args[0]); SimpleQueryRunner sqr = new SimpleQueryRunner(serverUri); sqr.options = new RequestOptions(); for (int i = 1; i < args.length; i++) { String query = QueryHelper.loadQueryFromFile(args[i]); if (args[i].endsWith(".js")) { sqr.options.setQueryLanguage("JavaScript"); } else { sqr.options.setQueryLanguage("XQuery"); } String result = sqr.executeToSingleString(query, System.getProperty("line.separator")); System.out.println(result); } } private static void usage() { System.err.println("usage: serverURL queryfile"); } }