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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package sun.tools.asm;
import sun.tools.java.*;
import sun.tools.tree.StringExpression;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Vector;
import java.io.IOException;
import java.io.DataOutputStream;
/**
* A table of constants
*
* WARNING: The contents of this source file are not part of any
* supported API. Code that depends on them does so at its own risk:
* they are subject to change or removal without notice.
*/
public final
class ConstantPool implements RuntimeConstants {
Hashtable<Object, ConstantPoolData> hash = new Hashtable<>(101);
/**
* Find an entry, may return 0
*/
public int index(Object obj) {
return hash.get(obj).index;
}
/**
* Add an entry
*/
public void put(Object obj) {
ConstantPoolData data = hash.get(obj);
if (data == null) {
if (obj instanceof String) {
data = new StringConstantData(this, (String)obj);
} else if (obj instanceof StringExpression) {
data = new StringExpressionConstantData(this, (StringExpression)obj);
} else if (obj instanceof ClassDeclaration) {
data = new ClassConstantData(this, (ClassDeclaration)obj);
} else if (obj instanceof Type) {
data = new ClassConstantData(this, (Type)obj);
} else if (obj instanceof MemberDefinition) {
data = new FieldConstantData(this, (MemberDefinition)obj);
} else if (obj instanceof NameAndTypeData) {
data = new NameAndTypeConstantData(this, (NameAndTypeData)obj);
} else if (obj instanceof Number) {
data = new NumberConstantData(this, (Number)obj);
}
hash.put(obj, data);
}
}
/**
* Write to output
*/
public void write(Environment env, DataOutputStream out) throws IOException {
ConstantPoolData list[] = new ConstantPoolData[hash.size()];
String keys[] = new String[list.length];
int index = 1, count = 0;
// Make a list of all the constant pool items
for (int n = 0 ; n < 5 ; n++) {
int first = count;
for (Enumeration<ConstantPoolData> e = hash.elements() ; e.hasMoreElements() ;) {
ConstantPoolData data = e.nextElement();
if (data.order() == n) {
keys[count] = sortKey(data);
list[count++] = data;
}
}
xsort(list, keys, first, count-1);
}
// Assign an index to each constant pool item
for (int n = 0 ; n < list.length ; n++) {
ConstantPoolData data = list[n];
data.index = index;
index += data.width();
}
// Write length
out.writeShort(index);
// Write each constant pool item
for (int n = 0 ; n < count ; n++) {
list[n].write(env, out, this);
}
}
private
static String sortKey(ConstantPoolData f) {
if (f instanceof NumberConstantData) {
Number num = ((NumberConstantData)f).num;
String str = num.toString();
int key = 3;
if (num instanceof Integer) key = 0;
else if (num instanceof Float) key = 1;
else if (num instanceof Long) key = 2;
return "\0" + (char)(str.length() + key<<8) + str;
}
if (f instanceof StringExpressionConstantData)
return (String)((StringExpressionConstantData)f).str.getValue();
if (f instanceof FieldConstantData) {
MemberDefinition fd = ((FieldConstantData)f).field;
return fd.getName()+" "+fd.getType().getTypeSignature()
+" "+fd.getClassDeclaration().getName();
}
if (f instanceof NameAndTypeConstantData)
return ((NameAndTypeConstantData)f).name+
" "+((NameAndTypeConstantData)f).type;
if (f instanceof ClassConstantData)
return ((ClassConstantData)f).name;
return ((StringConstantData)f).str;
}
/**
* Quick sort an array of pool entries and a corresponding array of Strings
* that are the sort keys for the field.
*/
private
static void xsort(ConstantPoolData ff[], String ss[], int left, int right) {
if (left >= right)
return;
String pivot = ss[left];
int l = left;
int r = right;
while (l < r) {
while (l <= right && ss[l].compareTo(pivot) <= 0)
l++;
while (r >= left && ss[r].compareTo(pivot) > 0)
r--;
if (l < r) {
// swap items at l and at r
ConstantPoolData def = ff[l];
String name = ss[l];
ff[l] = ff[r]; ff[r] = def;
ss[l] = ss[r]; ss[r] = name;
}
}
int middle = r;
// swap left and middle
ConstantPoolData def = ff[left];
String name = ss[left];
ff[left] = ff[middle]; ff[middle] = def;
ss[left] = ss[middle]; ss[middle] = name;
xsort(ff, ss, left, middle-1);
xsort(ff, ss, middle + 1, right);
}
}