[转] 范型是这样的-3
- import java.io.IOException;
- import java.io.Serializable;
- import java.io.Writer;
- import java.lang.reflect.GenericArrayType;
- import java.lang.reflect.Method;
- import java.lang.reflect.Modifier;
- import java.lang.reflect.ParameterizedType;
- import java.lang.reflect.Type;
- import java.lang.reflect.TypeVariable;
- import java.lang.reflect.WildcardType;
- import java.util.ArrayList;
- import java.util.List;
- /*******************************************************************************
- *
- *
- * @作者:XXX
- * @日期:2007-3-11
- * @版权:北京易迈普技术有限公司版权所有
- ******************************************************************************/
- public class GenericsTypeScanner {
- private Writer writer;
- public GenericsTypeScanner() {
- }
- /**
- * scan a generic class,output the originate declaration to the destination
- * writer。
- *
- * @param writer
- * @param clazz
- */
- public void 扫描(Writer writer, Class clazz) {
- this.writer = writer;
- try {
- printClass(clazz);
- for (Method method : clazz.getDeclaredMethods())
- printMethod(method);
- } catch (IOException e) {
- e.printStackTrace(System.out);
- }
- }
- private void printClass(Class clazz) throws IOException {
- writer.write(clazz.getName());
- printTypes(clazz.getTypeParameters(), “</span><span>”,
- “</span><span class=\”string\”>”,
- “</span><span>, </span><span class=\”string\”>”);
- // scan the super class
- Type superClazz = clazz.getGenericSuperclass();
- if (superClazz != null) {
- writer.write(” extends “);
- printType(superClazz);
- }
- // scan the interfaces
- printTypes(clazz.getGenericInterfaces(), ” implements “, “,”, “”);
- writer.write(“\n”);
- }
- private void printMethod(Method method) throws IOException {
- String name = method.getName();
- writer.write(Modifier.toString(method.getModifiers()));
- writer.write(” “);
- printTypes(method.getTypeParameters(), “</span><span>”,
- “</span><span class=\”string\”>”,
- “</span><span>, </span><span class=\”string\”>”);
- printType(method.getGenericReturnType());
- writer.write(” “);
- writer.write(name);
- writer.write(“(“);
- printTypes(method.getGenericParameterTypes(), “”, “, “, “”);
- writer.write(“)\n”);
- }
- private void printTypes(Type[] types, String prefix, String seperator,
- String suffix) throws IOException {
- if (types.length > 0)
- writer.write(prefix);
- for (int i = 0; i < types.length; i++) {
- if (i > 0)
- writer.write(seperator);
- printType(types[i]);
- }
- if (types.length > 0)
- writer.write(suffix);
- }
- private void printType(Type type) throws IOException {
- if (type instanceof Class) {
- Class t = (Class) type;
- writer.write(t.getName());
- } else if (type instanceof TypeVariable) {
- TypeVariable t = (TypeVariable) type;
- writer.write(t.getName());
- printTypes(t.getBounds(), ” extends “, “,”, “”);
- } else if (type instanceof WildcardType) {
- WildcardType t = (WildcardType) type;
- writer.write(“?”);
- printTypes(t.getLowerBounds(), ” extends “, ” & “, “”);
- printTypes(t.getUpperBounds(), ” super “, ” & “, “”);
- } else if (type instanceof ParameterizedType) {
- ParameterizedType t = (ParameterizedType) type;
- Type owner = t.getOwnerType();
- if (owner != null) {
- printType(owner);
- writer.write(“.”);
- }
- printType(t.getRawType());
- printTypes(t.getActualTypeArguments(), “</span><span>”,
- “</span><span class=\”string\”>”,
- “</span><span>, </span><span class=\”string\”>”);
- } else if (type instanceof GenericArrayType) {
- GenericArrayType t = (GenericArrayType) type;
- printType(t.getGenericComponentType());
- writer.write(“[]”);
- }
- }
- }