typedef struct{
int col_size;
char* data;
}J_ROW_DATA;
typedef struct{
int col_cnt;
J_ROW_DATA* col;
}J_ROW;
// Struct
void jreplace(J_ROW* row)
{
R2WR_ROW src; // our struct
R2WR_ROW dst;
int col_cnt = row->col_cnt;
int rv,j,i;
memset( &src, 0x00, sizeof(R2WR_ROW) );
for( j = 0; j < col_cnt; j++ ) {
src.col = (R2WR_COL*)realloc( src.col, sizeof(R2WR_COL)*(j+1) );
if( !src.col ) {
printf("Memory allocation failed.<%d>\n", j);
break;
}
memset( &(src.col[j]), 0x00, sizeof(R2WR_COL) );
///// .......
///// row->col[x].data setting
}
// interface.c file
###### JNA接口java public static class J_ROW_DATA extends Structure{
public static class ByReference extends J_ROW_DATA implements Structure.ByReference{}
public int col_size = 0;
public Pointer data;
public List getFieldOrder()
{
String[] s = new String[] { "col_size" ,"data" };
return Arrays.asList(s);
}
}
public static class J_ROW extends Structure
{
public static class ByReference extends J_ROW implements
Structure.ByReference{}
public static class ByValue extends J_ROW implements
Structure.ByValue{}
public int col_cnt = 0;
public J_ROW_DATA.ByReference col;
@Override
public List getFieldOrder()
{
String[] s = new String[] { "col_cnt", "col" };
return Arrays.asList(s);
}
}
public void r2wr_place(J_ROW.ByReference row);
//这是declar Structure ;;
/* other source */
ArrayList<Object> transArray = null;
CLibrary.J_ROW.ByReference data = new CLibrary.J_ROW.ByReference();
data.col_cnt = colarray.size();
data.col = new CLibrary.J_ROW_DATA.ByReference();
CLibrary.J_ROW_DATA[] cols = (CLibrary.J_ROW_DATA[])data.col.toArray(data.col_cnt);
for(int i = 0; i < data.col_cnt; i++)
{
byte[] tempbyte= null;
if(colarray.get(i) == null){
tempbyte = new byte[0];
cols[i].col_size = 0;
}
else{
tempbyte = colarray.get(i);
cols[i].col_size = tempbyte.length;
}
ByteBuffer buf = ByteBuffer.allocateDirect(tempbyte.length);
buf.put(tempbyte);
buf.rewind();
cols[i].data = Native.getDirectBufferPointer(buf);
} // this is Java to C pass Structure member
CLibrary.INSTANCE.jreplace(data); // C Library call
transArray = getObjList(data ,md); // byte to Object
/////////////////////////////////////////////// ////////////////////////////////////
private ArrayList<Object> getObjList(CLibrary.J_ROW.ByReference row, ResultSetMetaDatamd)throws SQLException
{
ArrayList<Object> tmp = new ArrayList<Object>();
int size = row.col_cnt;
CLibrary.J_ROW_DATA[] cols = (CLibrary.J_ROW_DATA[])row.col.toArray(row.col_cnt);
for(int j = 0; j < size; j++)
{
byte[] column = cols[j].data.getByteArray(0, cols[j].col_size);
// Problem
// column value is not expected
// for example, 1. printf value in interface.c file is [223] , but get value after getByteArray is [] and value size is 3
// 2. interface.c file printf value is [3232] , but column value is [8*5?]
并非总是会发生，有时候确实会获得价值
测试数据计数为10000000 它发生随机重复计数...... 我该怎么办？