org.hibernate.LazyInitializationException: failed to lazily initialize

这个问题肯定是由于关联表之间加载方式配置不当引起的（这不是废话么），网上有很多是关于“一对多”和“多对一”引起的错误的解决方案，我这里说一下，我遇到的是“多对多”

修改前

// UserInfo
@ManyToMany(cascade=CascadeType.REFRESH, fetch = FetchType.LAZY)
@JoinTable(
            name="user_role",
            joinColumns=@JoinColumn(name="user_id"),
            inverseJoinColumns=@JoinColumn(name="role_id")
)
public List getRoles() {
    return roles;
}

public void setRoles(List roles) {
    this.roles = roles;
}

// Role
@ManyToMany(cascade = {CascadeType.MERGE, CascadeType.PERSIST}, fetch = FetchType.LAZY)
    @JoinTable(
           name="user_role",
           joinColumns=@JoinColumn(name="role_id"),
           inverseJoinColumns=@JoinColumn(name="user_id"))
public List getUserInfos() {
    return userInfos;
}

public void setUserInfos(List userInfos) {
    this.userInfos = userInfos;
}

修改后

// UserInfo
@ManyToMany(cascade=CascadeType.REFRESH, fetch = FetchType.EAGER)
@JoinTable(
            name="user_role",
            joinColumns=@JoinColumn(name="user_id"),
            inverseJoinColumns=@JoinColumn(name="role_id")
)
public List getRoles() {
    return roles;
}

public void setRoles(List roles) {
    this.roles = roles;
}

// Role
@ManyToMany(cascade = {CascadeType.MERGE, CascadeType.PERSIST}, fetch = FetchType.LAZY,         
    targetEntity = UserInfo.class)
    @JoinTable(
           name="user_role",
           joinColumns=@JoinColumn(name="role_id"),
           inverseJoinColumns=@JoinColumn(name="user_id"))
public List getUserInfos() {
    return userInfos;
}

public void setUserInfos(List userInfos) {
    this.userInfos = userInfos;
}

引起问题的主要原因是因为UserInfo中关于到Role的加载策略使用了懒加载，结果在登录成功后就获取User对应Role时就出现在 org.hibernate.LazyInitializationException: failed to lazily initialize XXXXX could not initialize proxy - no Session错误，只需要将懒加载改为急加载即可