com.aspectran.core.util.ToStringBuilder Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2019 The Aspectran Project
*
* 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
*
* http://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 com.aspectran.core.util;
import com.aspectran.core.util.apon.Parameters;
import java.lang.reflect.Array;
import java.util.Collection;
import java.util.Enumeration;
import java.util.Map;
/**
* This class enables a good and consistent toString() to be built for any class or object.
*
* @author Juho Jeong
* @since 2016. 2. 11.
*/
public class ToStringBuilder {
private StringBuilder sb;
private final int start;
public ToStringBuilder() {
this(null);
}
public ToStringBuilder(String name) {
this(name, 32);
}
public ToStringBuilder(int capacity) {
this(null, capacity);
}
public ToStringBuilder(String name, int capacity) {
this.sb = new StringBuilder(capacity);
if (name != null) {
this.sb.append(name).append(" ");
this.start = sb.length() + 1;
} else {
this.start = 1;
}
this.sb.append("{");
}
public void append(String name, Object value) {
if (value != null) {
appendName(name);
append(value);
}
}
public void append(String name, Class clazz) {
if (clazz != null) {
appendName(name);
append(clazz.getName());
}
}
public void appendForce(String name, Object value) {
appendName(name);
append(value);
}
public void append(String name, boolean value) {
if (value) {
appendName(name);
this.sb.append(true);
}
}
public void appendForce(String name, boolean value) {
appendName(name);
this.sb.append(value);
}
public void appendEqual(String name, Object value, Object compare) {
if (value != null && value.equals(compare)) {
appendName(name);
append(value);
}
}
public void appendNotEqual(String name, Object value, Object compare) {
if (value != null && !value.equals(compare)) {
appendName(name);
append(value);
}
}
public void appendSize(String name, Object object) {
if (object != null) {
appendName(name);
if (object instanceof Map) {
this.sb.append(((Map)object).size());
} else if (object instanceof Collection) {
this.sb.append(((Collection)object).size());
} else if (object.getClass().isArray()) {
this.sb.append(Array.getLength(object));
} else if (object instanceof CharSequence) {
this.sb.append(((CharSequence)object).length());
}
}
}
private void appendName(Object name) {
appendName(name, this.start);
}
private void appendName(Object name, int start) {
if (this.sb.length() > start) {
appendComma();
}
this.sb.append(name).append("=");
}
private void appendComma() {
this.sb.append(", ");
}
private void append(Object object) {
if (object == null) {
this.sb.append((Object)null);
} else if (object instanceof Map) {
append((Map)object);
} else if (object instanceof Collection) {
append((Collection)object);
} else if (object instanceof Enumeration) {
append((Enumeration)object);
} else if (object instanceof Parameters) {
this.sb.append(((Parameters)object).describe(false));
} else if (object instanceof ToStringBuilder) {
this.sb.append(((ToStringBuilder)object).getStringBuilder());
} else if (object instanceof CharSequence) {
this.sb.append(((CharSequence)object));
} else if (object.getClass().isArray()) {
this.sb.append("[");
int len = Array.getLength(object);
for (int i = 0; i < len; i++) {
Object value = Array.get(object, i);
checkCircularReference(object, value);
if (i > 0) {
appendComma();
}
append(value);
}
this.sb.append("]");
} else {
this.sb.append(object);
}
}
private void append(Map map) {
if (map != null) {
this.sb.append("{");
int len = this.sb.length();
for (Map.Entry entry : ((Map)map).entrySet()) {
Object key = entry.getKey();
Object value = entry.getValue();
if (value != null) {
appendName(key, len);
append(value);
}
}
this.sb.append("}");
}
}
private void append(Collection list) {
if (list != null) {
this.sb.append("[");
int len = this.sb.length();
for (Object o : list) {
if (this.sb.length() > len) {
appendComma();
}
append(o);
}
this.sb.append("]");
}
}
private void append(Enumeration en) {
if (en != null) {
this.sb.append("[");
while (en.hasMoreElements()) {
append(en.nextElement());
if (en.hasMoreElements()) {
appendComma();
}
}
this.sb.append("]");
}
}
@Override
public String toString() {
this.sb.append("}");
return this.sb.toString();
}
protected StringBuilder getStringBuilder() {
return this.sb;
}
private void checkCircularReference(Object wrapper, Object member) {
if (wrapper.equals(member)) {
throw new IllegalArgumentException("Serialization Failure: A circular reference was detected " +
"while converting a member object [" + member + "] in [" + wrapper + "]");
}
}
}