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Copy pathSolution.java
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162 lines (128 loc) · 4.85 KB
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//Sanctify them in your truth. Your word is truth. (John 17:17)
package com.javarush.task.task17.task1717;
/*
Лишняя синхронизация
*/
public class Solution {
char[] value;
int count;
public Solution append(CharSequence s) {
// synchronized (Solution.class) {
if (s == null) {
// synchronized (this) {
s = "null";
// }
}
if (s instanceof String) {
// synchronized (this) {
return this.append((String) s);
// }
}
if (s instanceof Solution) {
// synchronized (this) {
return this.appendThis((Solution) s);
// }
}
// }
return this.append(s);
}
public synchronized Solution appendThis(Solution s) {
//do something here....
return this;
}
private static final java.io.ObjectStreamField[] serialPersistentFields =
{
new java.io.ObjectStreamField("value", char[].class),
new java.io.ObjectStreamField("count", Integer.TYPE),
new java.io.ObjectStreamField("shared", Boolean.TYPE),
};
private synchronized void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException {
java.io.ObjectOutputStream.PutField fields = s.putFields();
// synchronized (fields) {
fields.put("value", value);
fields.put("count", count);
fields.put("shared", false);
// }
// synchronized (s) {
s.writeFields();
// }
}
private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException {
// synchronized (new java.io.IOException()) {
java.io.ObjectInputStream.GetField fields = s.readFields();
value = (char[]) fields.get("value", null);
count = fields.get("count", 0);
// }
}
public static void main(String[] args) {
}
}
/*
Лишняя синхронизация
synchronized существенно замедляет программу, поэтому убери избыточность synchronized внутри методов
Требования:
1. Метод append(CharSequence s) класса Solution не должен быть synchronized.
2. Метод appendThis(Solution s) класса Solution должен быть synchronized.
3. Метод writeObject(java.io.ObjectOutputStream s) класса Solution должен быть synchronized.
4. Метод readObject(java.io.ObjectInputStream s) класса Solution не должен быть synchronized.
5. Метод main(String[] args) класса Solution не должен быть synchronized.
6. В классе Solution не должно быть synchronized блоков.
package com.javarush.task.task17.task1717;
/*
Лишняя синхронизация
*/
public class Solution {
char[] value;
int count;
public Solution append(CharSequence s) {
synchronized (Solution.class) {
if (s == null) {
synchronized (this) {
s = "null";
}
}
if (s instanceof String) {
synchronized (this) {
return this.append((String) s);
}
}
if (s instanceof Solution) {
synchronized (this) {
return this.appendThis((Solution) s);
}
}
}
return this.append(s);
}
public synchronized Solution appendThis(Solution s) {
//do something here....
return this;
}
private static final java.io.ObjectStreamField[] serialPersistentFields =
{
new java.io.ObjectStreamField("value", char[].class),
new java.io.ObjectStreamField("count", Integer.TYPE),
new java.io.ObjectStreamField("shared", Boolean.TYPE),
};
private synchronized void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException {
java.io.ObjectOutputStream.PutField fields = s.putFields();
synchronized (fields) {
fields.put("value", value);
fields.put("count", count);
fields.put("shared", false);
}
synchronized (s) {
s.writeFields();
}
}
private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException {
synchronized (new java.io.IOException()) {
java.io.ObjectInputStream.GetField fields = s.readFields();
value = (char[]) fields.get("value", null);
count = fields.get("count", 0);
}
}
public static void main(String[] args) {
}
}
*/