天津理工大学-操作系统-存储器的分配与回收算法实现-实验报告
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人郛數大学实验报告
实验内容:
实验过程记录（源程序、测试用例、测试结果及心得体会等）】
源程序:
MemoryBlock.java:
// 内存块类，包含各种操作
public class MemoryBlock {
static final int BLOCK_SIZE = 4096;
private int baseBlock; // 内存块基地
址
private int blockNum; // 大小
private boolean inUse; // 是否已分配
private MemoryBlock prev, next;
public MemoryBlock( int blockNum) { this .baseBlock = 0;
this .blockNum = blockNum;
inUse = false ;
prev = null ;
next = null ;
}
public MemoryBlock( int base, int blockNum) { this .baseBlock = base;
this .blockNum = blockNum;
inUse = false ;
prev = null
next = null
public int getBlockNum() { return blockNum;
}
public void setBlockNum( int blockNum) { this .blockNum = blockNum;
public MemoryBlock getPrev() { return prev;
}
public void setPrev(MemoryBlock prev) { this .prev = prev;
}
public MemoryBlock getNext() {
return next;
}
public void setNext(MemoryBlock next) { this .next = next;
}
public boolean inUse() { return inUse;
}
public void setUse() { inUse = true ;
}
public void free() {
inUse = false
public int getBaseBlock() {
return baseBlock;
public void setBaseBlock( int baseBlock) { this .baseBlock = baseBlock;
}
// 分配内存块，如果可分配，则返回剩余内存块public MemoryBlock allocate( int blockNum) { if (this .blockNum - blockNum>0) {
int newBase = baseBlock + blockNum;
int newBlock = this .blockNum-blockNum;
this .blockNum = blockNum;
setUse();
return new MemoryBlock(newBase, newBlock);
}
else if (this .blockNum - blockNum ==0) {
this .blockNum = 0;
}
return null ;
}
// 判断内存块是否能合并
public boolean merge(MemoryBlock memBlock) {
if (baseBlock+blockNum==memBlock.getBaseBlock()) { setBlockNum(blockNum+memBlock.blockNum);
memBlock.setBaseBlock(0);
memBlock.setBlockNum(0);
return true ;
}
else
return false ;
}
@Override
public String toString() {
String inUse = null ;
if (inUse())inUse = "已分配";
else inUse = "未分配";
return "内存块[基地址=" + baseBlock + ", 大小=" + blockNum +
", " + inUse + "]";
}
MemoryTable.java:
// 虚类MemTable ，提供内存链表的各种基本方法
public abstract class MemoryTable {
//MemoryBlock 链表表头
protected MemoryBlock memList;
public MemoryTable( int blockNum) {
memList = new MemoryBlock(0, blockNum);
}
// 把newBlock 插入到memBlock 前面
public void insertBefore(MemoryBlock memBlock, MemoryBlock newBlock){ if (memBlock.getPrev() != null )
memBlock.getPrev().setNext(newBlock);
if (memList == memBlock)
memList = newBlock;
newBlock.setPrev(memBlock.getPrev());