org.springframework.core.style.DefaultValueStyler Maven / Gradle / Ivy
/*
* Copyright 2002-2012 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.core.style;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
import org.springframework.util.ObjectUtils;
/**
* Converts objects to String form, generally for debugging purposes,
* using Spring's {@code toString} styling conventions.
*
* Uses the reflective visitor pattern underneath the hood to nicely
* encapsulate styling algorithms for each type of styled object.
*
* @author Keith Donald
* @author Juergen Hoeller
* @since 1.2.2
*/
public class DefaultValueStyler implements ValueStyler {
private static final String EMPTY = "[empty]";
private static final String NULL = "[null]";
private static final String COLLECTION = "collection";
private static final String SET = "set";
private static final String LIST = "list";
private static final String MAP = "map";
private static final String ARRAY = "array";
@Override
public String style(@Nullable Object value) {
if (value == null) {
return NULL;
}
else if (value instanceof String) {
return "\'" + value + "\'";
}
else if (value instanceof Class) {
return ClassUtils.getShortName((Class) value);
}
else if (value instanceof Method) {
Method method = (Method) value;
return method.getName() + "@" + ClassUtils.getShortName(method.getDeclaringClass());
}
else if (value instanceof Map) {
return style((Map) value);
}
else if (value instanceof Map.Entry) {
return style((Map.Entry) value);
}
else if (value instanceof Collection) {
return style((Collection) value);
}
else if (value.getClass().isArray()) {
return styleArray(ObjectUtils.toObjectArray(value));
}
else {
return String.valueOf(value);
}
}
private String style(Map value) {
StringBuilder result = new StringBuilder(value.size() * 8 + 16);
result.append(MAP + "[");
for (Iterator> it = value.entrySet().iterator(); it.hasNext();) {
Map.Entry entry = it.next();
result.append(style(entry));
if (it.hasNext()) {
result.append(',').append(' ');
}
}
if (value.isEmpty()) {
result.append(EMPTY);
}
result.append("]");
return result.toString();
}
private String style(Map.Entry value) {
return style(value.getKey()) + " -> " + style(value.getValue());
}
private String style(Collection value) {
StringBuilder result = new StringBuilder(value.size() * 8 + 16);
result.append(getCollectionTypeString(value)).append('[');
for (Iterator i = value.iterator(); i.hasNext();) {
result.append(style(i.next()));
if (i.hasNext()) {
result.append(',').append(' ');
}
}
if (value.isEmpty()) {
result.append(EMPTY);
}
result.append("]");
return result.toString();
}
private String getCollectionTypeString(Collection value) {
if (value instanceof List) {
return LIST;
}
else if (value instanceof Set) {
return SET;
}
else {
return COLLECTION;
}
}
private String styleArray(Object[] array) {
StringBuilder result = new StringBuilder(array.length * 8 + 16);
result.append(ARRAY + "<").append(ClassUtils.getShortName(array.getClass().getComponentType())).append(">[");
for (int i = 0; i < array.length - 1; i++) {
result.append(style(array[i]));
result.append(',').append(' ');
}
if (array.length > 0) {
result.append(style(array[array.length - 1]));
}
else {
result.append(EMPTY);
}
result.append("]");
return result.toString();
}
}