| 1 | /* |
| 2 | * Copyright 2007 brunella ltd |
| 3 | * |
| 4 | * Licensed under the LGPL Version 3 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * |
| 7 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| 8 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 9 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 10 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| 11 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 12 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 13 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 14 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 15 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 16 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| 17 | * THE POSSIBILITY OF SUCH DAMAGE. |
| 18 | */ |
| 19 | package sf.qof.util; |
| 20 | |
| 21 | import java.lang.reflect.Constructor; |
| 22 | import java.lang.reflect.GenericArrayType; |
| 23 | import java.lang.reflect.Method; |
| 24 | import java.lang.reflect.ParameterizedType; |
| 25 | import java.lang.reflect.Type; |
| 26 | import java.util.Collection; |
| 27 | import java.util.HashMap; |
| 28 | import java.util.Map; |
| 29 | import java.util.Set; |
| 30 | |
| 31 | import net.sf.cglib.core.Signature; |
| 32 | |
| 33 | import sf.qof.exception.ValidationException; |
| 34 | |
| 35 | /** |
| 36 | * Utility class for reflection functionality. |
| 37 | */ |
| 38 | public final class ReflectionUtils { |
| 39 | |
| 40 | private ReflectionUtils() { } |
| 41 | |
| 42 | /** |
| 43 | * Returns the getter method for a field name in a specified class. |
| 44 | * |
| 45 | * @param type the class |
| 46 | * @param fieldName field name |
| 47 | * @return getter method for a field or null |
| 48 | */ |
| 49 | public static Method findGetter(Class<?> type, String fieldName) { |
| 50 | try { |
| 51 | return type.getMethod(createGetterName(fieldName), (Class[]) null); |
| 52 | } catch (SecurityException e) { |
| 53 | } catch (NoSuchMethodException e) { |
| 54 | } |
| 55 | try { |
| 56 | Method method = type.getMethod(createIsGetterName(fieldName), (Class[]) null); |
| 57 | if (method.getReturnType() == Boolean.class || method.getReturnType() == Boolean.TYPE) { |
| 58 | return method; |
| 59 | } |
| 60 | } catch (SecurityException e) { |
| 61 | } catch (NoSuchMethodException e) { |
| 62 | } |
| 63 | return null; |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * Returns the setter method for a field name in a specified class. |
| 68 | * |
| 69 | * @param type the class |
| 70 | * @param fieldName field name |
| 71 | * @return setter method for a field or null |
| 72 | */ |
| 73 | public static Method findSetter(Class<?> type, String fieldName) { |
| 74 | String setterName = createSetterName(fieldName); |
| 75 | Method[] methods = type.getDeclaredMethods(); |
| 76 | for (Method method : methods) { |
| 77 | if (method.getName().equals(setterName)) { |
| 78 | return method; |
| 79 | } |
| 80 | } |
| 81 | return null; |
| 82 | } |
| 83 | |
| 84 | /** |
| 85 | * Returns the setter method for a field name in a specified class |
| 86 | * that uses a parameter of a type in a set. |
| 87 | * |
| 88 | * @param type the class |
| 89 | * @param fieldName field name |
| 90 | * @param mappableTypes set of all mappable types |
| 91 | * @return setter method for a field or null |
| 92 | */ |
| 93 | public static Method findSetter(Class<?> type, String fieldName, Set<Class<?>> mappableTypes) { |
| 94 | if (mappableTypes == null) { |
| 95 | return findSetter(type, fieldName); |
| 96 | } |
| 97 | String setterName = createSetterName(fieldName); |
| 98 | for (Class<?> mappableType : mappableTypes) { |
| 99 | try { |
| 100 | return type.getMethod(setterName, new Class[] { mappableType }); |
| 101 | } catch (SecurityException e) { |
| 102 | // ignore |
| 103 | } catch (NoSuchMethodException e) { |
| 104 | // ignore |
| 105 | } |
| 106 | } |
| 107 | return null; |
| 108 | } |
| 109 | |
| 110 | private static String createGetterName(String fieldName) { |
| 111 | return "get" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1); |
| 112 | } |
| 113 | |
| 114 | private static String createIsGetterName(String fieldName) { |
| 115 | return "is" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1); |
| 116 | } |
| 117 | |
| 118 | private static String createSetterName(String fieldName) { |
| 119 | return "set" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1); |
| 120 | } |
| 121 | |
| 122 | /** |
| 123 | * Returns the collection or map type of a type. |
| 124 | * |
| 125 | * @param type the type |
| 126 | * @return the collection type or null |
| 127 | */ |
| 128 | public static Class<?> getCollectionType(Type type) { |
| 129 | if (type instanceof ParameterizedType) { |
| 130 | Class<?> rawType = (Class<?>) ((ParameterizedType) type).getRawType(); |
| 131 | if ((Collection.class.isAssignableFrom(rawType) || |
| 132 | Map.class.isAssignableFrom(rawType)) && type != void.class) { |
| 133 | return rawType; |
| 134 | } |
| 135 | } |
| 136 | return null; |
| 137 | } |
| 138 | |
| 139 | /** |
| 140 | * Returns the array component type of a type. |
| 141 | * |
| 142 | * @param type the type |
| 143 | * @return the array component type or null |
| 144 | */ |
| 145 | public static Class<?> getArrayComponentType(Type type) { |
| 146 | if (type instanceof Class<?>) { |
| 147 | Class<?> clazz = (Class<?>)type; |
| 148 | if (clazz.isArray()) { |
| 149 | return clazz.getComponentType(); |
| 150 | } |
| 151 | } else if (type instanceof GenericArrayType) { |
| 152 | Type componentType = ((GenericArrayType)type).getGenericComponentType(); |
| 153 | if (componentType instanceof Class<?>) { |
| 154 | return (Class<?>)componentType; |
| 155 | } |
| 156 | } |
| 157 | return null; |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * Returns the parameterized type of a collection type. |
| 162 | * For example if <code>type</code> is <code>List<String></code> |
| 163 | * this method returns <code>String</code>. If <code>type</code> is |
| 164 | * <code>Map<int, String></code> it returns <code>String</code>. |
| 165 | * |
| 166 | * @param type the parameterized type |
| 167 | * @return the parameterized type |
| 168 | * @throws ValidationException if type is not parameterized |
| 169 | */ |
| 170 | public static Class<?> getCollectionParameterizedType(Type type) { |
| 171 | if (type instanceof ParameterizedType) { |
| 172 | ParameterizedType parameterizedType = (ParameterizedType) type; |
| 173 | int numTypeArguments = parameterizedType.getActualTypeArguments().length; |
| 174 | if (numTypeArguments == 1) { |
| 175 | return (Class<?>) parameterizedType.getActualTypeArguments()[0]; |
| 176 | } else if (numTypeArguments == 2) { |
| 177 | return (Class<?>) parameterizedType.getActualTypeArguments()[1]; |
| 178 | } else { |
| 179 | throw new ValidationException("Collection parameterized type must be one for " + type); |
| 180 | } |
| 181 | } else { |
| 182 | throw new ValidationException("Collection " + type + " must be parameterized"); |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | /** |
| 187 | * Returns the key type of a parameterized type. |
| 188 | * For example if <code>type</code> is <code>Map<int, String></code> |
| 189 | * it returns <code>int</code>. |
| 190 | * |
| 191 | * @param type the parameterized type |
| 192 | * @return the key type |
| 193 | */ |
| 194 | public static Class<?> getCollectionParameterizedKeyType(Type type) { |
| 195 | if (type instanceof ParameterizedType) { |
| 196 | ParameterizedType parameterizedType = (ParameterizedType) type; |
| 197 | if (parameterizedType.getActualTypeArguments().length != 2) { |
| 198 | return null; |
| 199 | } |
| 200 | return (Class<?>) parameterizedType.getActualTypeArguments()[0]; |
| 201 | } else { |
| 202 | return null; |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | private static final Map<Class<?>, Class<?>> BOXED_CLASSES; |
| 207 | private static final Map<Class<?>, Class<?>> UNBOXED_CLASSES; |
| 208 | static { |
| 209 | BOXED_CLASSES = new HashMap<Class<?>, Class<?>>(8); |
| 210 | BOXED_CLASSES.put(Byte.class, Byte.TYPE); |
| 211 | BOXED_CLASSES.put(Short.class, Short.TYPE); |
| 212 | BOXED_CLASSES.put(Integer.class, Integer.TYPE); |
| 213 | BOXED_CLASSES.put(Long.class, Long.TYPE); |
| 214 | BOXED_CLASSES.put(Boolean.class, Boolean.TYPE); |
| 215 | BOXED_CLASSES.put(Float.class, Float.TYPE); |
| 216 | BOXED_CLASSES.put(Double.class, Double.TYPE); |
| 217 | BOXED_CLASSES.put(Void.class, Void.TYPE); |
| 218 | |
| 219 | UNBOXED_CLASSES = new HashMap<Class<?>, Class<?>>(8); |
| 220 | for (Class<?> boxed : BOXED_CLASSES.keySet()) { |
| 221 | UNBOXED_CLASSES.put(BOXED_CLASSES.get(boxed), boxed); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | /** |
| 226 | * Returns the unboxed type of a specified type. |
| 227 | * Types that are not boxed are returned unchanged. |
| 228 | * |
| 229 | * @param type the type |
| 230 | * @return unboxed type |
| 231 | */ |
| 232 | public static Class<?> unbox(Class<?> type) { |
| 233 | Class<?> returnClass = BOXED_CLASSES.get(type); |
| 234 | return returnClass == null ? type : returnClass; |
| 235 | } |
| 236 | |
| 237 | /** |
| 238 | * Returns the boxed type of a specified primitive type. |
| 239 | * Types that are not primitive types are returned unchanged. |
| 240 | * |
| 241 | * @param type the type |
| 242 | * @return boxed type |
| 243 | */ |
| 244 | public static Class<?> box(Class<?> type) { |
| 245 | Class<?> returnClass = UNBOXED_CLASSES.get(type); |
| 246 | return returnClass == null ? type : returnClass; |
| 247 | } |
| 248 | |
| 249 | /** |
| 250 | * Returns a method <code>Signature</code> object for a <code>Method</code> parameter. |
| 251 | * |
| 252 | * @param method the method |
| 253 | * @return a method signature |
| 254 | */ |
| 255 | public static Signature getMethodSignature(Method method) { |
| 256 | Class<?>[] params = method.getParameterTypes(); |
| 257 | org.objectweb.asm.Type[] paramTypes = new org.objectweb.asm.Type[params.length]; |
| 258 | for (int i = 0; i < params.length; i++) { |
| 259 | paramTypes[i] = org.objectweb.asm.Type.getType(params[i]); |
| 260 | } |
| 261 | |
| 262 | return new Signature(method.getName(), org.objectweb.asm.Type.getType(method.getReturnType()), paramTypes); |
| 263 | } |
| 264 | |
| 265 | /** |
| 266 | * Returns a constructor <code>Signature</code> object for a <code>Constructor</code> parameter. |
| 267 | * |
| 268 | * @param constructor the constructor |
| 269 | * @return a constructor signature |
| 270 | */ |
| 271 | public static Signature getConstructorSignature(Constructor<?> constructor) { |
| 272 | Class<?>[] params = constructor.getParameterTypes(); |
| 273 | org.objectweb.asm.Type[] paramTypes = new org.objectweb.asm.Type[params.length]; |
| 274 | for (int i = 0; i < params.length; i++) { |
| 275 | paramTypes[i] = org.objectweb.asm.Type.getType(params[i]); |
| 276 | } |
| 277 | |
| 278 | return new Signature("<init>", org.objectweb.asm.Type.VOID_TYPE, paramTypes); |
| 279 | } |
| 280 | |
| 281 | } |