java/src/main/java/com/jsoniter/TypeLiteral.java at master · androiddream/java · GitHub

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package com.jsoniter;

import java.lang.reflect.ParameterizedType;

import java.lang.reflect.Type;

public class TypeLiteral<T> {

final Type type;

final String cacheKey;

/**

* Constructs a new type literal. Derives represented class from type parameter.

* Clients create an empty anonymous subclass. Doing so embeds the type parameter in the

* anonymous class's type hierarchy so we can reconstitute it at runtime despite erasure.

@SuppressWarnings("unchecked")

protected TypeLiteral() {

this.type = getSuperclassTypeParameter(getClass());

cacheKey = generateCacheKey(type);

}

public static String generateCacheKey(Type type) {

StringBuilder decoderClassName = new StringBuilder("codegen.");

if (type instanceof Class) {

Class clazz = (Class) type;

decoderClassName.append(clazz.getCanonicalName().replace("[]", "_array"));

} else if (type instanceof ParameterizedType) {

ParameterizedType pType = (ParameterizedType) type;

Class clazz = (Class) pType.getRawType();

decoderClassName.append(clazz.getCanonicalName().replace("[]", "_array"));

for (int i = 0; i < pType.getActualTypeArguments().length; i++) {

String typeName = formatTypeWithoutSpecialCharacter(pType.getActualTypeArguments()[i]);

decoderClassName.append('_');

decoderClassName.append(typeName);

}

} else {

throw new UnsupportedOperationException("do not know how to handle: " + type);

}

return decoderClassName.toString().replace("$", "_");

}

private static String formatTypeWithoutSpecialCharacter(Type type) {

if (type instanceof Class) {

Class clazz = (Class) type;

return clazz.getCanonicalName();

}

if (type instanceof ParameterizedType) {

ParameterizedType pType = (ParameterizedType) type;

String typeName = formatTypeWithoutSpecialCharacter(pType.getRawType());

for (Type typeArg : pType.getActualTypeArguments()) {

typeName += "_";

typeName += formatTypeWithoutSpecialCharacter(typeArg);

}

return typeName;

}

throw new RuntimeException("unsupported type: " + type);

}

static Type getSuperclassTypeParameter(Class<?> subclass) {

Type superclass = subclass.getGenericSuperclass();

if (superclass instanceof Class) {

throw new RuntimeException("Missing type parameter.");

}

ParameterizedType parameterized = (ParameterizedType) superclass;

return parameterized.getActualTypeArguments()[0];

}

public Type getType() {

return type;

}

public String getCacheKey() {

return cacheKey;

}

java/src/main/java/com/jsoniter/TypeLiteral.java at master · androiddream/java · GitHub

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