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QuestDB is High Performance Time Series Database
/*******************************************************************************
* ___ _ ____ ____
* / _ \ _ _ ___ ___| |_| _ \| __ )
* | | | | | | |/ _ \/ __| __| | | | _ \
* | |_| | |_| | __/\__ \ |_| |_| | |_) |
* \__\_\\__,_|\___||___/\__|____/|____/
*
* Copyright (C) 2014-2016 Appsicle
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see Class loadClass(Class host) {
byte b[] = new byte[position()];
System.arraycopy(buf.array(), 0, b, 0, b.length);
return (Class) Unsafe.getUnsafe().defineAnonymousClass(host, b, null);
}
public int poolClass(int classIndex) {
put(0x07);
putShort(classIndex);
return poolCount++;
}
public int poolClass(Class clazz) {
String name = clazz.getName();
put(0x01);
int n;
putShort(n = name.length());
for (int i = 0; i < n; i++) {
char c = name.charAt(i);
switch (c) {
case '.':
put('/');
break;
default:
put(c);
break;
}
}
return poolClass(this.poolCount++);
}
public int poolField(int classIndex, int nameAndTypeIndex) {
return poolRef(0x09, classIndex, nameAndTypeIndex);
}
public int poolInterfaceMethod(int classIndex, int nameAndTypeIndex) {
return poolRef(0x0B, classIndex, nameAndTypeIndex);
}
public int poolMethod(int classIndex, int nameAndTypeIndex) {
return poolRef(0x0A, classIndex, nameAndTypeIndex);
}
public int poolNameAndType(int nameIndex, int typeIndex) {
return poolRef(0x0C, nameIndex, typeIndex);
}
public Utf8Appender poolUtf8() {
put(0x01);
utf8Appender.lenpos = position();
utf8Appender.utf8len = 0;
putShort(0);
return utf8Appender;
}
public int poolUtf8(CharSequence cs) {
put(0x01);
int n;
putShort(n = cs.length());
for (int i = 0; i < n; i++) {
put(cs.charAt(i));
}
return this.poolCount++;
}
public int position() {
return buf.position();
}
public void put(int b) {
if (buf.remaining() == 0) {
resize();
}
buf.put((byte) b);
}
public void putConstant(int v) {
if (v > -1 && v < 6) {
put(iconst_0 + v);
} else if (v < 0) {
put(sipush);
putShort(v);
} else if (v < 128) {
put(bipush);
put(v);
} else {
put(sipush);
putShort(v);
}
}
public void putShort(int v) {
putShort((short) v);
}
public void putShort(int pos, int v) {
buf.putShort(pos, (short) v);
}
public void putStackMapAppendInt(int stackMapTableIndex, int position) {
putShort(stackMapTableIndex);
int lenPos = position();
// length - we will come back here
putInt(0);
// number of entries
putShort(1);
// frame type APPEND
put(0xFC);
// offset delta - points at branch target
putShort(position);
// type: int
put(0x01);
// fix attribute length
putInt(lenPos, position() - lenPos - 4);
}
public void setupPool() {
// magic
putInt(0xCAFEBABE);
// version
putInt(0x33);
// skip pool count, write later when we know the value
putShort(0);
// add standard stuff
objectClassIndex = poolClass(Object.class);
defaultConstructorMethodIndex = poolMethod(objectClassIndex, poolNameAndType(
defaultConstructorNameIndex = poolUtf8(""),
defaultConstructorDescIndex = poolUtf8("()V"))
);
codeAttributeIndex = poolUtf8("Code");
}
public void startMethod(int flags, int nameIndex, int descriptorIndex, int maxStack, int maxLocal) {
// access flags
putShort(flags);
// name index
putShort(nameIndex);
// descriptor index
putShort(descriptorIndex);
// attribute count
putShort(1);
// code
putShort(codeAttributeIndex);
// come back to this later
this.methodCut1 = position();
// attribute len
putInt(0);
// max stack
putShort(maxStack);
// max locals
putShort(maxLocal);
// code len
this.methodCut2 = position();
putInt(0);
}
private int poolRef(int op, int name, int type) {
put(op);
putShort(name);
putShort(type);
return poolCount++;
}
private void putInt(int pos, int v) {
buf.putInt(pos, v);
}
private void putInt(int v) {
if (buf.remaining() < 4) {
resize();
}
buf.putInt(v);
}
private void putShort(short v) {
if (buf.remaining() < 2) {
resize();
}
buf.putShort(v);
}
private void resize() {
ByteBuffer b = ByteBuffer.allocate(buf.capacity() * 2).order(ByteOrder.BIG_ENDIAN);
System.arraycopy(buf.array(), 0, b.array(), 0, buf.capacity());
b.position(buf.position());
buf = b;
}
public class Utf8Appender extends AbstractCharSink implements CharSink {
private int utf8len = 0;
private int lenpos;
public int $() {
putShort(lenpos, utf8len);
return poolCount++;
}
@Override
public void flush() throws IOException {
}
@Override
public Utf8Appender put(CharSequence cs) {
int n = cs.length();
for (int i = 0; i < n; i++) {
BytecodeAssembler.this.put(cs.charAt(i));
}
utf8len += n;
return this;
}
@Override
public Utf8Appender put(char c) {
BytecodeAssembler.this.put(c);
utf8len++;
return this;
}
@Override
public Utf8Appender put(int value) {
super.put(value);
return this;
}
}
}