package com.xxx.utils;import java.lang.reflect.Field;import java.lang.reflect.Modifier;import java.util.List;import java.util.Vector;import org.apache.commons.lang3.reflect.FieldUtils;public class ModelToSQL {    private Object target;    private String idName;    private Object idValue;    private SqlType currentType;    public enum SqlType {        INSERT, UPDATE, DELETE    }    public ModelToSQL(SqlType sqlType, Object target) {        this.target = target;        switch (sqlType) {        case INSERT:            currentType = SqlType.INSERT;            createInsert();            break;        case UPDATE:            currentType = SqlType.UPDATE;            createUpdate();            break;        case DELETE:            currentType = SqlType.DELETE;            createDelete();            break;        }    }    public ModelToSQL(Class
      target) {        String tableName = getTableNameForClass(target);        getFields(target);        StringBuffer sqlBuffer = new StringBuffer();        sqlBuffer.append("DELETE FROM ").append(tableName).append(" WHERE ");        for (Field field : fields) {            if (!Modifier.isStatic(field.getModifiers())) {                ID id = field.getAnnotation(ID.class);                if (null != id) {                    sqlBuffer.append(field.getName()).append("=?");                }            }        }        this.sqlBuffer = sqlBuffer.toString();    }    /**     * 创建跟删除     */    private void createDelete() {        String tableName = getTableName();        getFields(target.getClass());        StringBuffer sqlBuffer = new StringBuffer();        sqlBuffer.append("DELETE FROM ").append(tableName).append(" WHERE ");        for (Field field : fields) {            if (!Modifier.isStatic(field.getModifiers())) {                ID id = field.getAnnotation(ID.class);                if (null != id) {                    sqlBuffer.append(field.getName()).append(" = ? ");                    param.add(readField(field));                }            }        }        System.err.println("delete:\t"+sqlBuffer.toString());        this.sqlBuffer = sqlBuffer.toString();    }    protected Object readField(Field field) {        try {            return FieldUtils.readField(field, target, true);        } catch (Exception e) {            throw new RuntimeException(currentType.name(), e);        }    }    /**     * 创建更新语句     */    private void createUpdate() {        String tableName = getTableName();        getFields(target.getClass());        StringBuffer sqlBuffer = new StringBuffer();        sqlBuffer.append("UPDATE ").append(tableName).append(" SET ");        for (Field field : fields) {            if (!Modifier.isStatic(field.getModifiers())) {                ID id = field.getAnnotation(ID.class);                if (id == null) {                    sqlBuffer.append(field.getName()).append("=? , ");                    param.add(readField(field));                } else {                    idName = field.getName();                    idValue = readField(field);                }            }        }        sqlBuffer.replace(sqlBuffer.length()-2, sqlBuffer.length()-1, " ");        if (idName == null) {            throw new RuntimeException("not found of " + target.getClass() + "'s ID");        }        sqlBuffer.append(" WHERE ").append(idName).append("=?");        param.add(idValue);System.err.println("update:\t"+sqlBuffer.toString());        this.sqlBuffer = sqlBuffer.toString();    }    /**     * 根据注解获取表名     */    private String getTableName() {        String tableName = null;        Class
      clazz = target.getClass();        tableName = getTableNameForClass(clazz);        return tableName;    }    private String getTableNameForClass(Class
      clazz) {        String tableName;        Table table = clazz.getAnnotation(Table.class);        if (null != table) {            tableName = table.name();            if ("".equalsIgnoreCase(tableName)) {                tableName = clazz.getSimpleName();            }        } else {            tableName = clazz.getSimpleName();        }        return tableName;    }    /**     * 创建插入语句     */    private void createInsert() {        String tableName = getTableName();        getFields(target.getClass());        StringBuffer sqlBuffer = new StringBuffer();        sqlBuffer.append("INSERT INTO ").append(tableName).append("(");        for (Field field : fields) {            if (!Modifier.isStatic(field.getModifiers())) {                ID id = field.getAnnotation(ID.class);                if (id == null) {                    sqlBuffer.append(field.getName()).append(",");                    param.add(readField(field));                }            }        }        int length = sqlBuffer.length();        sqlBuffer.delete(length - 1, length).append(")values(");        int size = param.size();        for (int x = 0; x < size; x++) {            if (x != 0) {                sqlBuffer.append(",");            }            sqlBuffer.append("?");        }        sqlBuffer.append(")");System.err.println("insert:\t"+sqlBuffer.toString());        this.sqlBuffer = sqlBuffer.toString();    }    private List