Java example source code file (genclass.clj)

This example Java source code file (genclass.clj) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

arraydefinterface, arraygeninterface, deprecated, exampleannotationclass, exampleclass, illegalargumentexception, java, protectedfinaltester, retention, string, stringbuilder, stuart, target

The genclass.clj Java example source code

;   Copyright (c) Rich Hickey. All rights reserved.
;   The use and distribution terms for this software are covered by the
;   Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
;   which can be found in the file epl-v10.html at the root of this distribution.
;   By using this software in any fashion, you are agreeing to be bound by
;   the terms of this license.
;   You must not remove this notice, or any other, from this software.

(ns ^{:doc "Tests for clojure.core/gen-class"
      :author "Stuart Halloway, Daniel Solano Gómez"}
  clojure.test-clojure.genclass
  (:use clojure.test clojure.test-helper)
  (:require clojure.test_clojure.genclass.examples)
  (:import [clojure.test_clojure.genclass.examples
            ExampleClass
            ExampleAnnotationClass
            ProtectedFinalTester
            ArrayDefInterface
            ArrayGenInterface]

           [java.lang.annotation ElementType
                                 Retention
                                 RetentionPolicy
                                 Target]))

(deftest arg-support
  (let [example (ExampleClass.)
        o (Object.)]
    (is (= "foo with o, o" (.foo example o o)))
    (is (= "foo with o, i" (.foo example o (int 1))))
    (is (thrown? java.lang.UnsupportedOperationException (.foo example o)))))

(deftest name-munging
  (testing "mapping from Java fields to Clojure vars"
    (is (= #'clojure.test-clojure.genclass.examples/-foo-Object-int
           (get-field ExampleClass 'foo_Object_int__var)))
    (is (= #'clojure.test-clojure.genclass.examples/-toString
           (get-field ExampleClass 'toString__var)))))

;todo - fix this, it depends on the order of things out of a hash-map
#_(deftest test-annotations
  (let [annot-class ExampleAnnotationClass
        foo-method          (.getDeclaredMethod annot-class "foo" (into-array [String]))]
    (testing "Class annotations:"
      (is (= 2 (count (.getDeclaredAnnotations annot-class))))
      (testing "@Deprecated"
        (let [deprecated (.getAnnotation annot-class Deprecated)]
          (is deprecated)))
      (testing "@Target([])"
        (let [resource (.getAnnotation annot-class Target)]
          (is (= 0 (count (.value resource)))))))
    (testing "Method annotations:"
      (testing "@Deprecated void foo(String):"
        (is (= 1 (count (.getDeclaredAnnotations foo-method))))
        (is (.getAnnotation foo-method Deprecated))))
    (testing "Parameter annotations:"
      (let [param-annots (.getParameterAnnotations foo-method)]
        (is (= 1 (alength param-annots)))
        (let [first-param-annots (aget param-annots 0)]
          (is (= 2 (alength first-param-annots)))
          (testing "void foo(@Retention(…) String)"
            (let [retention (aget first-param-annots 0)]
              (is (instance? Retention retention))
              (= RetentionPolicy/SOURCE (.value retention))))
          (testing "void foo(@Target(…) String)"
            (let [target (aget first-param-annots 1)]
              (is (instance? Target target))
              (is (= [ElementType/TYPE ElementType/PARAMETER] (seq (.value target)))))))))))

(deftest genclass-option-validation
  (is (fails-with-cause? IllegalArgumentException #"Not a valid method name: has-hyphen"
        (@#'clojure.core/validate-generate-class-options {:methods '[[fine [] void] [has-hyphen [] void]]}))))

(deftest protected-final-access
  (let [obj (ProtectedFinalTester.)]
    (testing "Protected final method visibility"
      (is (thrown? IllegalArgumentException (.findSystemClass obj "java.lang.String"))))
    (testing "Allow exposition of protected final method."
      (is (= String (.superFindSystemClass obj "java.lang.String"))))))

(deftest interface-array-type-hints
  (let [array-types       {:ints     (class (int-array 0))
                           :bytes    (class (byte-array 0))
                           :shorts   (class (short-array 0))
                           :chars    (class (char-array 0))
                           :longs    (class (long-array 0))
                           :floats   (class (float-array 0))
                           :doubles  (class (double-array 0))
                           :booleans (class (boolean-array 0))
                           :maps     (class (into-array java.util.Map []))}
        array-types       (assoc array-types
                                 :maps-2d (class (into-array (:maps array-types) [])))
        method-with-name  (fn [name methods] (first (filter #(= name (.getName %)) methods)))
        parameter-type    (fn [method] (first (.getParameterTypes method)))
        return-type       (fn [method] (.getReturnType method))]
    (testing "definterface"
      (let [method-with-name #(method-with-name % (.getMethods ArrayDefInterface))]
        (testing "sugar primitive array hints"
          (are [name type] (= (type array-types)
                              (parameter-type (method-with-name name)))
               "takesByteArray"    :bytes
               "takesCharArray"    :chars
               "takesShortArray"   :shorts
               "takesIntArray"     :ints
               "takesLongArray"    :longs
               "takesFloatArray"   :floats
               "takesDoubleArray"  :doubles
               "takesBooleanArray" :booleans))
        (testing "raw primitive array hints"
          (are [name type] (= (type array-types)
                              (return-type (method-with-name name)))
               "returnsByteArray"    :bytes
               "returnsCharArray"    :chars
               "returnsShortArray"   :shorts
               "returnsIntArray"     :ints
               "returnsLongArray"    :longs
               "returnsFloatArray"   :floats
               "returnsDoubleArray"  :doubles
               "returnsBooleanArray" :booleans))))
    (testing "gen-interface"
      (let [method-with-name #(method-with-name % (.getMethods ArrayGenInterface))]
        (testing "sugar primitive array hints"
          (are [name type] (= (type array-types)
                              (parameter-type (method-with-name name)))
               "takesByteArray"    :bytes
               "takesCharArray"    :chars
               "takesShortArray"   :shorts
               "takesIntArray"     :ints
               "takesLongArray"    :longs
               "takesFloatArray"   :floats
               "takesDoubleArray"  :doubles
               "takesBooleanArray" :booleans))
        (testing "raw primitive array hints"
          (are [name type] (= (type array-types)
                              (return-type (method-with-name name)))
               "returnsByteArray"    :bytes
               "returnsCharArray"    :chars
               "returnsShortArray"   :shorts
               "returnsIntArray"     :ints
               "returnsLongArray"    :longs
               "returnsFloatArray"   :floats
               "returnsDoubleArray"  :doubles
               "returnsBooleanArray" :booleans))))))

(deftest gen-interface-source-file
  (let [classReader (clojure.asm.ClassReader. "clojure.test_clojure.genclass.examples.ArrayGenInterface")
        sourceFile (StringBuilder.)
        sourceVisitor (proxy [clojure.asm.ClassVisitor] [clojure.asm.Opcodes/ASM4 nil]
                        (visitSource [source debug] (.append sourceFile source)))]
    (.accept classReader sourceVisitor 0)
    (is (= "examples.clj" (str sourceFile)))))