io.polaris.core.converter.ArrayConverter Maven / Gradle / Ivy
package io.polaris.core.converter;
import io.polaris.core.collection.Iterables;
import io.polaris.core.consts.SymbolConsts;
import io.polaris.core.io.Serializations;
import io.polaris.core.json.JsonSerializer;
import io.polaris.core.lang.JavaType;
import io.polaris.core.log.ILogger;
import io.polaris.core.log.ILoggers;
import io.polaris.core.service.StatefulServiceLoader;
import java.io.Serializable;
import java.lang.reflect.Array;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.Type;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Optional;
/**
* @author Qt
* @since 1.8
*/
public class ArrayConverter extends AbstractConverter {
private static final ILogger log = ILoggers.of(ArrayConverter.class);
private final JavaType targetType;
private final JavaType targetComponentType;
public ArrayConverter(Class targetType) {
this(targetType == null ? null : JavaType.of(targetType));
}
public ArrayConverter(JavaType targetType) {
if (targetType == null) {
// 默认Object数组
this.targetType = JavaType.of((Type) Object[].class);
this.targetComponentType = JavaType.of((Type) Object.class);
} else {
if (targetType.getRawType() instanceof GenericArrayType) {
this.targetType = targetType;
this.targetComponentType = JavaType.of(((GenericArrayType) targetType.getRawType()).getGenericComponentType());
} else if (targetType.getRawClass().isArray()) {
this.targetType = targetType;
this.targetComponentType = JavaType.of((Type) targetType.getRawClass().getComponentType());
} else {
//用户传入类为非数组时，按照数组元素类型对待
this.targetComponentType = JavaType.of(targetType.getRawType());
this.targetType = JavaType.of(new GenericArrayType() {
@Override
public Type getGenericComponentType() {
return targetComponentType.getRawType();
}
@Override
public String toString() {
return targetComponentType.getRawType().getTypeName() + "[]";
}
});
}
}
}
@Override
public JavaType getTargetType() {
return this.targetType;
}
@Override
protected T[] doConvert(S value, JavaType targetType, JavaType sourceType) {
if (sourceType.getRawType() instanceof Class) {
if (((Class) sourceType.getRawType()).isArray() && targetComponentType.getRawClass().isAssignableFrom(((Class) sourceType.getRawType()).getComponentType())) {
return (T[]) value;
}
} else if (sourceType.getRawType() instanceof GenericArrayType) {
Type genericComponentType = ((GenericArrayType) sourceType.getRawType()).getGenericComponentType();
if (this.targetComponentType == genericComponentType) {
return (T[]) value;
}
}
return (T[]) (value.getClass().isArray() ? convertArrayToArray(value) : convertObjectToArray(value));
}
private Object convertArrayToArray(Object array) {
final int len = Array.getLength(array);
final Object result = Array.newInstance(targetComponentType.getRawClass(), len);
for (int i = 0; i < len; i++) {
Array.set(result, i, convertComponentType(Array.get(array, i)));
}
return result;
}
private String[] splitCharSequence(CharSequence value) {
int begin = 0;
int end = value.length();
for (int i = 0; i < value.length(); i++) {
char ch = value.charAt(i);
if (Character.isWhitespace(ch)) {
begin = i;
} else {
if (ch == '[') {
begin = i + 1;
}
break;
}
}
for (int i = value.length() - 1; i >= 0; i--) {
char ch = value.charAt(i);
if (Character.isWhitespace(ch)) {
end = i;
} else {
if (ch == ']') {
end = i;
}
break;
}
}
if (end > begin) {
return value.subSequence(begin, end).toString().trim().split(SymbolConsts.COMMA);
} else {
return new String[]{""};
}
}
private Object convertObjectToArray(Object value) {
if (value instanceof CharSequence) {
if (targetComponentType.getRawClass() == char.class || targetComponentType.getRawClass() == Character.class) {
return convertArrayToArray(value.toString().toCharArray());
}
try {
// 扩展json实现，
Optional optional = StatefulServiceLoader.load(JsonSerializer.class).optionalService();
if (optional.isPresent()) {
String json = value.toString();
return optional.get().deserialize(json, targetType.getRawType());
}
} catch (Exception e) {
log.warn("解析JSON失败：{}", e.getMessage());
if (log.isDebugEnabled()) {
log.debug(e.getMessage(), e);
}
}
return convertArrayToArray(splitCharSequence((CharSequence) value));
}
if (value instanceof List) {
// List转数组
List list = (List) value;
Object result = Array.newInstance(targetComponentType.getRawClass(), list.size());
for (int i = 0; i < list.size(); i++) {
Array.set(result, i, convertComponentType(list.get(i)));
}
return result;
}
if (value instanceof Collection) {
// 集合转数组
Collection collection = (Collection) value;
Object result = Array.newInstance(targetComponentType.getRawClass(), collection.size());
int i = 0;
for (Object element : collection) {
Array.set(result, i, convertComponentType(element));
i++;
}
return result;
}
if (value instanceof Iterable) {
List list = Iterables.asList((Iterable) value);
Object result = Array.newInstance(targetComponentType.getRawClass(), list.size());
for (int i = 0; i < list.size(); i++) {
Array.set(result, i, convertComponentType(list.get(i)));
}
return result;
}
if (value instanceof Iterator) {
List list = Iterables.asList((Iterator) value);
Object result = Array.newInstance(targetComponentType.getRawClass(), list.size());
for (int i = 0; i < list.size(); i++) {
Array.set(result, i, convertComponentType(list.get(i)));
}
return result;
}
if (value instanceof Serializable && byte.class == targetComponentType.getRawClass()) {
// 用户可能想序列化指定对象
return Serializations.serialize(value);
}
return convertToSingleElementArray(value);
}
private Object convertToSingleElementArray(Object value) {
final Object result = Array.newInstance(targetComponentType.getRawClass(), 1);
Array.set(result, 0, convertComponentType(value));
return result;
}
private Object convertComponentType(Object value) {
return Converters.convert(this.targetComponentType, value, null);
}
}