Array Operations

public class ByteArrayMethods {
    public static long nextPowerOf2(long num);
    public static int roundNumberOfBytesToNearestWord(int numBytes);
    public static long roundNumberOfBytesToNearestWord(long numBytes);
    public static boolean arrayEquals(Object leftBase, long leftOffset, Object rightBase, long rightOffset, long length);
    public static boolean contains(byte[] arr, byte[] sub);
    public static boolean startsWith(byte[] array, byte[] target);
    public static boolean endsWith(byte[] array, byte[] target);
    public static boolean matchAt(byte[] arr, byte[] sub, int pos);
    
    public static final int MAX_ROUNDED_ARRAY_LENGTH;
}

public final class LongArray {
    public LongArray(MemoryBlock memory);
    public MemoryBlock memoryBlock();
    public Object getBaseObject();
    public long getBaseOffset();
    public long size();
    public void zeroOut();
    public void set(int index, long value);
    public long get(int index);
}

public abstract class KVIterator<K, V> {
    public abstract boolean next() throws IOException;
    public abstract K getKey();
    public abstract V getValue();
    public abstract void close();
}

import org.apache.spark.unsafe.array.ByteArrayMethods;

// Power of 2 calculations for memory alignment
long size = ByteArrayMethods.nextPowerOf2(1000); // Returns 1024
int rounded = ByteArrayMethods.roundNumberOfBytesToNearestWord(15); // Aligns to word boundary

// Array comparison and search operations
byte[] data = "Hello World".getBytes();
byte[] pattern = "World".getBytes();

boolean hasPattern = ByteArrayMethods.contains(data, pattern);
boolean startsWithHello = ByteArrayMethods.startsWith(data, "Hello".getBytes());
boolean endsWithWorld = ByteArrayMethods.endsWith(data, "World".getBytes());
boolean matchesAtPosition = ByteArrayMethods.matchAt(data, pattern, 6);

// High-performance array equality check
byte[] array1 = "test data".getBytes();
byte[] array2 = "test data".getBytes();
boolean equal = ByteArrayMethods.arrayEquals(
    array1, 0,           // Left base and offset
    array2, 0,           // Right base and offset  
    array1.length        // Length to compare
);

import org.apache.spark.unsafe.array.LongArray;
import org.apache.spark.unsafe.memory.MemoryAllocator;
import org.apache.spark.unsafe.memory.MemoryBlock;

// Create long array from allocated memory
MemoryAllocator allocator = MemoryAllocator.UNSAFE;
MemoryBlock memory = allocator.allocate(8 * 1000); // 1000 longs
LongArray array = new LongArray(memory);

// Array operations
long arraySize = array.size(); // Number of elements
array.zeroOut(); // Fill with zeros

// Set and get values (no bounds checking for performance)
for (int i = 0; i < arraySize; i++) {
    array.set(i, i * 2L);
}

long value = array.get(500); // Get value at index 500

// Access underlying memory
Object baseObject = array.getBaseObject();
long baseOffset = array.getBaseOffset();
MemoryBlock underlyingMemory = array.memoryBlock();

// Clean up
allocator.free(memory);

import org.apache.spark.unsafe.array.ByteArrayMethods;
import org.apache.spark.unsafe.Platform;

// Create two memory regions
long addr1 = Platform.allocateMemory(1000);
long addr2 = Platform.allocateMemory(1000);

// Fill with test data
Platform.setMemory(addr1, (byte) 0x42, 1000);
Platform.setMemory(addr2, (byte) 0x42, 1000);

// High-performance comparison
boolean equal = ByteArrayMethods.arrayEquals(
    null, addr1,    // Left base (null for off-heap) and offset
    null, addr2,    // Right base and offset
    1000            // Length
);

// Clean up
Platform.freeMemory(addr1);
Platform.freeMemory(addr2);

import org.apache.spark.unsafe.KVIterator;
import java.io.IOException;
import java.util.List;

// Example implementation for iterating over key-value pairs
public class ListKVIterator extends KVIterator<String, Integer> {
    private final List<Map.Entry<String, Integer>> entries;
    private int position = -1;
    
    public ListKVIterator(List<Map.Entry<String, Integer>> entries) {
        this.entries = entries;
    }
    
    @Override
    public boolean next() throws IOException {
        position++;
        return position < entries.size();
    }
    
    @Override
    public String getKey() {
        return entries.get(position).getKey();
    }
    
    @Override
    public Integer getValue() {
        return entries.get(position).getValue();
    }
    
    @Override
    public void close() {
        // Cleanup resources if needed
    }
}

// Usage
KVIterator<String, Integer> iterator = new ListKVIterator(keyValuePairs);
try {
    while (iterator.next()) {
        String key = iterator.getKey();
        Integer value = iterator.getValue();
        // Process key-value pair
    }
} finally {
    iterator.close();
}

import org.apache.spark.unsafe.array.ByteArrayMethods;

// Ensure memory allocations are word-aligned for optimal performance
int requestedSize = 123;
int alignedSize = ByteArrayMethods.roundNumberOfBytesToNearestWord(requestedSize);

// Use aligned size for memory allocation
long address = Platform.allocateMemory(alignedSize);

// Check maximum safe array length
int maxLength = ByteArrayMethods.MAX_ROUNDED_ARRAY_LENGTH;
if (requestedSize <= maxLength) {
    // Safe to allocate
}