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| package org.apache.xindice.util; |
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| import java.io.Serializable; |
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| public final class ObjectStack implements Serializable { |
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| static final long serialVersionUID = -7896992305408562521L; |
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| private ObjectStackItem last = null; |
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| private int size = 0; |
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170230
| public synchronized void push(Object value) {
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170231
| size++;
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170231
| ObjectStackItem q = new ObjectStackItem(value, last);
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170231
| last = q;
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| } |
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181329
| public synchronized Object pop() {
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| ObjectStackItem q = last;
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181329
| if (q != null) {
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170229
| size--;
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170229
| last = q.prev;
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170229
| return q.value;
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| } |
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11100
| return null;
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| } |
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0
| public boolean isEmpty() {
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| return (size == 0);
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| } |
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| public int size() {
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| return size;
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| } |
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| public synchronized Object peek() {
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| return last != null ? last.value
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| : null; |
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| } |
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| public synchronized void clear() {
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| size = 0;
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| last = null;
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| } |
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| private class ObjectStackItem implements Serializable { |
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| public Object value; |
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| public ObjectStackItem prev; |
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170231
| public ObjectStackItem(Object value, ObjectStackItem prev) {
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170231
| this.value = value;
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170231
| this.prev = prev;
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| } |
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| } |
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| } |