我正在为名为 Minecraft 的游戏制作一个插件Bukkit API。
我有一个Reinforcements使用以下字段调用的数据库表：x integer, y integer, z integer. 加固块是受保护的块，这意味着它不能被破坏。
我正在使用EntityExplodeEvent来检查 TNT 爆炸。
我遍历event.blocklist()并将每个块与 Reinforcements 表中的条目进行比较。如果存在，则使用 防止在爆炸中损坏加固块event.blocklist().remove。
我可以通过获取每个坐标 (x,y,z) 的最小和最大，然后检查这两个数字之间的数据库行来做到这一点。问题在于它是一个立方体。我应该检查一个球体。我该怎么做呢？
这是我到目前为止所得到的，请注意：我知道这并不是 select 语句的问题，因为我可以将返回的行与之进行比较，event.blocklist()但是当我进行更新时，我需要知道如何执行此操作稍后声明。
我需要知道如何检查球体中的行的原因是因为最终我将在 Reinforcements 表中添加一个额外的字段，称为'durability integer'该字段将在每次爆炸后递减。由于爆炸是一个球体，更新查询应该只更新该球体中的行，而不是一个立方体。
任何人？谢谢
当前 MySQL 查询
"SELECT X, Y, Z FROM REINFORCEMENTS WHERE DURABILITY >= 1 " +
"AND x<=? AND x>=? AND y<=? AND y>=? AND z<=? AND z>=? AND world=?");
完整代码
@EventHandler
public void checkForExplosion(EntityExplodeEvent event){
if(event.isCancelled()){
return;
}
//Store blocks that are inside explosion's blast radius
List<Block> blastRadiusBlocks = event.blockList();
//If explosion occurs in mid air it returns 0 so no need to go any
//further since there are no blocks inside the explosions radius
if(blastRadiusBlocks.size() < 1){
return;
}
HashMap<Coordinate, Block> affectedBlocks = new HashMap<Coordinate, Block>();
//Initialize min & max X,Y,Z coordinates
int smallestX = blastRadiusBlocks.get(0).getX();
int largestX = smallestX;
int smallestY = blastRadiusBlocks.get(0).getY();
int largestY = smallestY;
int smallestZ = blastRadiusBlocks.get(0).getZ();
int largestZ = smallestZ;
//World Name
String worldName = blastRadiusBlocks.get(0).getWorld().getName();
World world = this.myPlugin.getServer().getWorld(worldName);
//Find min & max X,Y,Z coordinates
for(int i = 0; i < blastRadiusBlocks.size(); i++){
Block block = blastRadiusBlocks.get(i);
int blockX = block.getX();
int blockY = block.getY();
int blockZ = block.getZ();
if(blockX < smallestX){
smallestX = blockX;
}
if(blockX > largestX){
largestX = blockX;
}
if(blockY < smallestY){
smallestY = blockY;
}
if(blockY > largestY){
largestY = blockY;
}
if(blockZ < smallestZ){
smallestZ = blockZ;
}
if(blockZ > largestZ){
largestZ = blockZ;
}
//Instantiate Coordinate class passing in parameters
Coordinate coordinate = new Coordinate(world, blockX, blockY, blockZ);
//Put a new entry of type Coordinate as key and type Block as value
affectedBlocks.put(coordinate, block);
}
try {
//Query database for any reinforced blocks that may be in the blast radius
//Reinforced blocks should have a durability > 0 (aka >= 1)
PreparedStatement ask = this.conn.prepareStatement(
"SELECT X, Y, Z FROM REINFORCEMENTS WHERE DURABILITY >= 1 " +
"AND x<=? AND x>=? AND y<=? AND y>=? AND z<=? AND z>=? AND world=?");
ask.setInt(1, largestX);
ask.setInt(2, smallestX);
ask.setInt(3, largestY);
ask.setInt(4, smallestY);
ask.setInt(5, largestZ);
ask.setInt(6, smallestZ);
ask.setString(7, worldName);
ask.execute();
ResultSet result = ask.getResultSet();
//If there was some found, loop through each one
while(result.next()){
//Get X,Y,Z coords of reinforced block
int x = result.getInt(1);
int y = result.getInt(2);
int z = result.getInt(3);
//Pass in x, y, z of reinforced block into affectedBlocks HashMap to instantiate a Block
Block protectedBlock = affectedBlocks.get(new Coordinate(world, x, y, z));
//Then remove the protectedBlock from explosion list
event.blockList().remove(protectedBlock);
}
result.close();
ask.close();
} catch (SQLException e) {
System.err.println("Citadel - Select Reinforcement can't keep up (possibly too many explosions):\n" + e);
}
}