/**
* 提取获取全局序列操作通用流程
*
* @param schema
* @param seqName
* @param count
* @param operation
* @return
*/
private long commonGetSeqVal(
String schema, String seqName, Long count, FETCH_OPERATION operation) {
long id = -1;
// 节点路径
String idPath = String.format("%s/%s/%s", ROOT_PATH, schema, seqName);
try {
if (checkNodeExisted(idPath, client)) {
client.sync(idPath, null); // 获取前，先从leader那里同步 !! 异步操作，但是有序 !!
DistributedAtomicLong dal = buildDAL(idPath, true);
switch (operation) {
// 获取当前全局序列值
case CURR:
AtomicValue<Long> currValue = dal.get();
if (currValue.succeeded()) {
id = currValue.postValue();
} else {
throw new AmoebaRuntimeException("fetch from id server error");
}
break;
// 获取下一个全局序列
case NEXT:
AtomicValue<Long> nextValue = dal.increment();
if (nextValue.succeeded()) {
id = nextValue.postValue();
} else {
throw new AmoebaRuntimeException("fetch from id server error");
}
break;
// 批量获取全局序列
case BATCH:
AtomicValue<Long> startValue = dal.get();
id = startValue.postValue() + count;
if (startValue.succeeded()) {
dal.forceSet(id);
}
break;
default:
throw new AmoebaRuntimeException("not support this fetch method");
}
} else {
throw new AmoebaRuntimeException(String.format("sequence %s is not existed", seqName));
}
} catch (Exception e) {
throw new AmoebaRuntimeException(e.getMessage());
}
return id;
}
/** 创建某个序列 */
@Override
public synchronized SeqOperationResult createSeq(
String schema, String seqName, long start, long offset) {
SeqOperationResult result = null;
// 节点路径
String idPath = String.format("%s/%s/%s", ROOT_PATH, schema, seqName);
try {
if (checkNodeExisted(idPath, client)) {
result = new SeqOperationResult(false, String.format("sequence %s is existed", seqName));
} else {
DistributedAtomicLong dal = buildDAL(idPath, false);
dal.forceSet(start);
result = new SeqOperationResult(true, "");
}
} catch (Exception e) {
throw new AmoebaRuntimeException(e.getMessage());
}
return result;
}