(get-value "<a><b>SOMETHING</b></a>)" "b")

"SOMETHING"

user=> (use 'clojure.xml)

user=> (for [x (xml-seq
          (parse (java.io.File. file)))
             :when (= :b (:tag x))]
     (first (:content x)))

(require '[net.cgrand.enlive-html :as html])

(map html/text
     (html/select (html/html-snippet "<a><b>SOMETHING</b></a>")  [:a :b]))

(import javax.xml.parsers.DocumentBuilderFactory)
(import javax.xml.xpath.XPathFactory)

(defn document [filename]
  (-> (DocumentBuilderFactory/newInstance)
      .newDocumentBuilder
      (.parse filename)))

(defn get-value [document xpath]
  (-> (XPathFactory/newInstance)
      .newXPath
      (.compile xpath)
      (.evaluate document)))

user=> (get-value (document "something.xml") "//a/b/text()")
"SOMETHING"

user=> (require '[clojure zip xml] '[clojure.contrib.zip-filter [xml :as x]])

user=> (def z (-> (.getBytes "<a><b>SOMETHING</b></a>")
                  java.io.ByteArrayInputStream.
                  clojure.xml/parse clojure.zip/xml-zip))

user=> (x/xml1-> z :b x/text)

"SOMETHING"

(use 'com.github.kyleburton.clj-xpath :only [$x:text])
($x:text "/a/b" "<a><b>SOMETHING</b></a>)")