HTTP.java

package play.utils;

import play.libs.IO;

import java.io.InputStream;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class HTTP {

    public static class ContentTypeWithEncoding {
        public final String contentType;
        public final String encoding;

        public ContentTypeWithEncoding(String contentType, String encoding) {
            this.contentType = contentType;
            this.encoding = encoding;
        }
    }

    public static ContentTypeWithEncoding parseContentType( String contentType ) {
        if( contentType == null ) {
            return new ContentTypeWithEncoding("text/html".intern(), null);
        } else {
            String[] contentTypeParts = contentType.split(";");
            String _contentType = contentTypeParts[0].trim().toLowerCase();
            String _encoding = null;
            // check for encoding-info
            if( contentTypeParts.length >= 2 ) {
                String[] encodingInfoParts = contentTypeParts[1].split(("="));
                if( encodingInfoParts.length == 2 && encodingInfoParts[0].trim().equalsIgnoreCase("charset")) {
                    // encoding-info was found in request
                    _encoding = encodingInfoParts[1].trim();
                }
            }
            return new ContentTypeWithEncoding(_contentType, _encoding);
        }

    }

    private static final Map<String, String> lower2UppercaseHttpHeaders = initLower2UppercaseHttpHeaders();

    private static Map<String, String> initLower2UppercaseHttpHeaders() {
        Map<String, String> map = new HashMap<String, String>();

        String path = "/play/utils/http_headers.properties";
        InputStream in = HTTP.class.getResourceAsStream(path);
        if (in == null) {
            throw new RuntimeException("Error reading " + path);
        }
        List<String> lines = IO.readLines( in );
        for (String line : lines) {
            line = line.trim();
            if ( !line.startsWith("#")) {
                map.put(line.toLowerCase(), line);
            }
        }

        return Collections.unmodifiableMap(map);
    }

    /**
     * Use this method to make sure you have the correct caseing of a http header name.
     * eg: fixes 'content-type' to 'Content-Type'
     */
    public static String fixCaseForHttpHeader( String headerName) {
        if (headerName == null) {
            return null;
        }
        String correctCase = lower2UppercaseHttpHeaders.get(headerName.toLowerCase());
        if ( correctCase != null) {
            return correctCase;
        }
        // Didn't find it - return it as it is
        return headerName;
    }
}