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LDK Java Bindings and Release Binaries
package org.ldk.structs;
import org.ldk.impl.bindings;
import org.ldk.enums.*;
import org.ldk.util.*;
import java.util.Arrays;
import java.lang.ref.Reference;
import javax.annotation.Nullable;
/**
* Provides an interface that allows storage and retrieval of persisted values that are associated
* with given keys.
*
* In order to avoid collisions the key space is segmented based on the given `primary_namespace`s
* and `secondary_namespace`s. Implementations of this trait are free to handle them in different
* ways, as long as per-namespace key uniqueness is asserted.
*
* Keys and namespaces are required to be valid ASCII strings in the range of
* [`KVSTORE_NAMESPACE_KEY_ALPHABET`] and no longer than [`KVSTORE_NAMESPACE_KEY_MAX_LEN`]. Empty
* primary namespaces and secondary namespaces (`\"\"`) are assumed to be a valid, however, if
* `primary_namespace` is empty, `secondary_namespace` is required to be empty, too. This means
* that concerns should always be separated by primary namespace first, before secondary
* namespaces are used. While the number of primary namespaces will be relatively small and is
* determined at compile time, there may be many secondary namespaces per primary namespace. Note
* that per-namespace uniqueness needs to also hold for keys *and* namespaces in any given
* namespace, i.e., conflicts between keys and equally named
* primary namespaces/secondary namespaces must be avoided.
*
* Note:** Users migrating custom persistence backends from the pre-v0.0.117 `KVStorePersister`
* interface can use a concatenation of `[{primary_namespace}/[{secondary_namespace}/]]{key}` to
* recover a `key` compatible with the data model previously assumed by `KVStorePersister::persist`.
*/
@SuppressWarnings("unchecked") // We correctly assign various generic arrays
public class KVStore extends CommonBase {
final bindings.LDKKVStore bindings_instance;
KVStore(Object _dummy, long ptr) { super(ptr); bindings_instance = null; }
private KVStore(bindings.LDKKVStore arg) {
super(bindings.LDKKVStore_new(arg));
this.ptrs_to.add(arg);
this.bindings_instance = arg;
}
@Override @SuppressWarnings("deprecation")
protected void finalize() throws Throwable {
if (ptr != 0) { bindings.KVStore_free(ptr); } super.finalize();
}
/**
* Destroys the object, freeing associated resources. After this call, any access
* to this object may result in a SEGFAULT or worse.
*
* You should generally NEVER call this method. You should let the garbage collector
* do this for you when it finalizes objects. However, it may be useful for types
* which represent locks and should be closed immediately to avoid holding locks
* until the GC runs.
*/
public void destroy() {
if (ptr != 0) { bindings.KVStore_free(ptr); }
ptr = 0;
}
public static interface KVStoreInterface {
/**
* Returns the data stored for the given `primary_namespace`, `secondary_namespace`, and
* `key`.
*
* Returns an [`ErrorKind::NotFound`] if the given `key` could not be found in the given
* `primary_namespace` and `secondary_namespace`.
*
* [`ErrorKind::NotFound`]: io::ErrorKind::NotFound
*/
Result_CVec_u8ZIOErrorZ read(String primary_namespace, String secondary_namespace, String key);
/**
* Persists the given data under the given `key`.
*
* Will create the given `primary_namespace` and `secondary_namespace` if not already present
* in the store.
*/
Result_NoneIOErrorZ write(String primary_namespace, String secondary_namespace, String key, byte[] buf);
/**
* Removes any data that had previously been persisted under the given `key`.
*
* If the `lazy` flag is set to `true`, the backend implementation might choose to lazily
* remove the given `key` at some point in time after the method returns, e.g., as part of an
* eventual batch deletion of multiple keys. As a consequence, subsequent calls to
* [`KVStore::list`] might include the removed key until the changes are actually persisted.
*
* Note that while setting the `lazy` flag reduces the I/O burden of multiple subsequent
* `remove` calls, it also influences the atomicity guarantees as lazy `remove`s could
* potentially get lost on crash after the method returns. Therefore, this flag should only be
* set for `remove` operations that can be safely replayed at a later time.
*
* Returns successfully if no data will be stored for the given `primary_namespace`,
* `secondary_namespace`, and `key`, independently of whether it was present before its
* invokation or not.
*/
Result_NoneIOErrorZ remove(String primary_namespace, String secondary_namespace, String key, boolean lazy);
/**
* Returns a list of keys that are stored under the given `secondary_namespace` in
* `primary_namespace`.
*
* Returns the keys in arbitrary order, so users requiring a particular order need to sort the
* returned keys. Returns an empty list if `primary_namespace` or `secondary_namespace` is unknown.
*/
Result_CVec_StrZIOErrorZ list(String primary_namespace, String secondary_namespace);
}
private static class LDKKVStoreHolder { KVStore held; }
public static KVStore new_impl(KVStoreInterface arg) {
final LDKKVStoreHolder impl_holder = new LDKKVStoreHolder();
impl_holder.held = new KVStore(new bindings.LDKKVStore() {
@Override public long read(String primary_namespace, String secondary_namespace, String key) {
Result_CVec_u8ZIOErrorZ ret = arg.read(primary_namespace, secondary_namespace, key);
Reference.reachabilityFence(arg);
long result = ret == null ? 0 : ret.clone_ptr();
return result;
}
@Override public long write(String primary_namespace, String secondary_namespace, String key, byte[] buf) {
Result_NoneIOErrorZ ret = arg.write(primary_namespace, secondary_namespace, key, buf);
Reference.reachabilityFence(arg);
long result = ret == null ? 0 : ret.clone_ptr();
return result;
}
@Override public long remove(String primary_namespace, String secondary_namespace, String key, boolean lazy) {
Result_NoneIOErrorZ ret = arg.remove(primary_namespace, secondary_namespace, key, lazy);
Reference.reachabilityFence(arg);
long result = ret == null ? 0 : ret.clone_ptr();
return result;
}
@Override public long list(String primary_namespace, String secondary_namespace) {
Result_CVec_StrZIOErrorZ ret = arg.list(primary_namespace, secondary_namespace);
Reference.reachabilityFence(arg);
long result = ret == null ? 0 : ret.clone_ptr();
return result;
}
});
return impl_holder.held;
}
/**
* Returns the data stored for the given `primary_namespace`, `secondary_namespace`, and
* `key`.
*
* Returns an [`ErrorKind::NotFound`] if the given `key` could not be found in the given
* `primary_namespace` and `secondary_namespace`.
*
* [`ErrorKind::NotFound`]: io::ErrorKind::NotFound
*/
public Result_CVec_u8ZIOErrorZ read(java.lang.String primary_namespace, java.lang.String secondary_namespace, java.lang.String key) {
long ret = bindings.KVStore_read(this.ptr, primary_namespace, secondary_namespace, key);
Reference.reachabilityFence(this);
Reference.reachabilityFence(primary_namespace);
Reference.reachabilityFence(secondary_namespace);
Reference.reachabilityFence(key);
if (ret >= 0 && ret <= 4096) { return null; }
Result_CVec_u8ZIOErrorZ ret_hu_conv = Result_CVec_u8ZIOErrorZ.constr_from_ptr(ret);
return ret_hu_conv;
}
/**
* Persists the given data under the given `key`.
*
* Will create the given `primary_namespace` and `secondary_namespace` if not already present
* in the store.
*/
public Result_NoneIOErrorZ write(java.lang.String primary_namespace, java.lang.String secondary_namespace, java.lang.String key, byte[] buf) {
long ret = bindings.KVStore_write(this.ptr, primary_namespace, secondary_namespace, key, buf);
Reference.reachabilityFence(this);
Reference.reachabilityFence(primary_namespace);
Reference.reachabilityFence(secondary_namespace);
Reference.reachabilityFence(key);
Reference.reachabilityFence(buf);
if (ret >= 0 && ret <= 4096) { return null; }
Result_NoneIOErrorZ ret_hu_conv = Result_NoneIOErrorZ.constr_from_ptr(ret);
return ret_hu_conv;
}
/**
* Removes any data that had previously been persisted under the given `key`.
*
* If the `lazy` flag is set to `true`, the backend implementation might choose to lazily
* remove the given `key` at some point in time after the method returns, e.g., as part of an
* eventual batch deletion of multiple keys. As a consequence, subsequent calls to
* [`KVStore::list`] might include the removed key until the changes are actually persisted.
*
* Note that while setting the `lazy` flag reduces the I/O burden of multiple subsequent
* `remove` calls, it also influences the atomicity guarantees as lazy `remove`s could
* potentially get lost on crash after the method returns. Therefore, this flag should only be
* set for `remove` operations that can be safely replayed at a later time.
*
* Returns successfully if no data will be stored for the given `primary_namespace`,
* `secondary_namespace`, and `key`, independently of whether it was present before its
* invokation or not.
*/
public Result_NoneIOErrorZ remove(java.lang.String primary_namespace, java.lang.String secondary_namespace, java.lang.String key, boolean lazy) {
long ret = bindings.KVStore_remove(this.ptr, primary_namespace, secondary_namespace, key, lazy);
Reference.reachabilityFence(this);
Reference.reachabilityFence(primary_namespace);
Reference.reachabilityFence(secondary_namespace);
Reference.reachabilityFence(key);
Reference.reachabilityFence(lazy);
if (ret >= 0 && ret <= 4096) { return null; }
Result_NoneIOErrorZ ret_hu_conv = Result_NoneIOErrorZ.constr_from_ptr(ret);
return ret_hu_conv;
}
/**
* Returns a list of keys that are stored under the given `secondary_namespace` in
* `primary_namespace`.
*
* Returns the keys in arbitrary order, so users requiring a particular order need to sort the
* returned keys. Returns an empty list if `primary_namespace` or `secondary_namespace` is unknown.
*/
public Result_CVec_StrZIOErrorZ list(java.lang.String primary_namespace, java.lang.String secondary_namespace) {
long ret = bindings.KVStore_list(this.ptr, primary_namespace, secondary_namespace);
Reference.reachabilityFence(this);
Reference.reachabilityFence(primary_namespace);
Reference.reachabilityFence(secondary_namespace);
if (ret >= 0 && ret <= 4096) { return null; }
Result_CVec_StrZIOErrorZ ret_hu_conv = Result_CVec_StrZIOErrorZ.constr_from_ptr(ret);
return ret_hu_conv;
}
}